EN(w/o STI)(diag)-96

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

18.Diagnostic Procedure with Diagnostic Trouble Code (DTC)

A: DTC P000A A CAMSHAFT POSITION SLOW RESPONSE (BANK 1)

NOTE:

For the diagnostic procedure, refer to DTC P0011. <Ref. to EN(w/o STI)(diag)-99, DTC P0011 INTAKE

CAMSHAFT POSITION - TIMING OVER-ADVANCED OR SYSTEM PERFORMANCE (BANK 1), Diagnostic

Procedure with Diagnostic Trouble Code (DTC).>

B: DTC P000B B CAMSHAFT POSITION SLOW RESPONSE (BANK 1)

NOTE:

For the diagnostic procedure, refer to DTC P0014. <Ref. to EN(w/o STI)(diag)-102, DTC P0014 EXHAUST

AVCS SYSTEM 1 (RANGE/PERFORMANCE), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

C: DTC P000C A CAMSHAFT POSITION SLOW RESPONSE (BANK 2)

NOTE:

For the diagnostic procedure, refer to DTC P0021. <Ref. to EN(w/o STI)(diag)-113, DTC P0021 INTAKE

CAMSHAFT POSITION - TIMING OVER-ADVANCED OR SYSTEM PERFORMANCE (BANK 2), Diagnostic

Procedure with Diagnostic Trouble Code (DTC).>

D: DTC P000D B CAMSHAFT POSITION SLOW RESPONSE (BANK 2)

NOTE:

For the diagnostic procedure, refer to DTC P0024. <Ref. to EN(w/o STI)(diag)-116, DTC P0024 EXHAUST

AVCS SYSTEM 2 (RANGE/PERFORMANCE), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

15WRX_STI_US_EN.book 96 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-97

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

E: DTC P0010 "A" CAMSHAFT POSITION ACTUATOR CIRCUIT/OPEN (BANK 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-15, DTC P0010 "A" CAMSHAFT POSITION ACTUA-

TOR CIRCUIT/OPEN (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK OUTPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 7 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E3B22

B550

215

B220

E38E37

E38

EN-10796

E159

215

E37

SBF-7

ECM

232221 262524201918

587

10 11

B550

INTAKE

OIL CONTROL

SOLENOID LH

INTAKE

OIL CONTROL

SOLENOID RH

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 97 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-98

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

3 CHECK POWER SUPPLY TO THE INTAKE

OIL CONTROL SOLENOID RH.

Measure the voltage between intake oil control

solenoid RH connector and engine ground.

Connector & terminal

(E38) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID RH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the ECM

and intake oil control solenoid RH.

3) Measure the resistance between intake oil

control solenoid RH connector and engine

ground.

Connector & terminal

(E38) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and intake oil con-

trol solenoid RH

connector.

5 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID RH CON-

NECTOR.

Measure the resistance of harness between

ECM connector and intake oil control solenoid

RH.

Connector & terminal

(E159) No. 7 — (E38) No. 2:

Is the resistance less than 1 Ω? Go to step 6. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and intake oil con-

trol solenoid RH

connector

• Poor contact of

coupling connector

6 CHECK INTAKE OIL CONTROL SOLENOID

RH.

Measure the resistance between intake oil con-

trol solenoid RH terminals.

Terminals

No. 1 — No. 2:

Is the resistance 6 — 12 Ω? Repair the poor

contact of intake oil

control solenoid

RH connector.

Replace the intake

oil control solenoid

RH. <Ref. to FU(w/

o STI)-108, Oil

Control Solenoid.>

Step Check Yes No

15WRX_STI_US_EN.book 98 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-99

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

F: DTC P0011 INTAKE CAMSHAFT POSITION - TIMING OVER-ADVANCED OR

SYSTEM PERFORMANCE (BANK 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-16, DTC P0011 INTAKE CAMSHAFT POSITION - TIM-

ING OVER-ADVANCED OR SYSTEM PERFORMANCE (BANK 1), Diagnostic Trouble Code (DTC) Detect-

ing Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 IDENTIFYING FAULTY PART.

1) Perform the Clear Memory Mode. <Ref. to

EN(w/o STI)(diag)-61, Clear Memory Mode.>

2) Replace the defective oil control solenoid by

the other (RH or LH, intake side or exhaust side)

oil control solenoid.

3) Perform appropriate drive cycle test. <Ref.

to EN(w/o STI)(diag)-50, Drive Cycle.>

4) Make sure that the fault occurrence (DTC

and incorrect advancing) has shifted to the

other location.

Did the detected DTC shift to

the location where the oil con-

trol solenoid was replaced?

Replace the faulty

oil control sole-

noid.

Go to step 2.

2 CHECK CURRENT DATA.

1) Start the engine and let it idle.

2) Read the value of «VVT Adv. Ang. Amount

R» using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

Is the value of «VVT Adv. Ang.

Amount R» approx. 0 deg?

Go to step 3. Check the follow-

ing item and repair

or replace if neces-

sary.

• Intake cam

sprocket (clog or

dirt of oil routing,

setting of spring)

• Intake camshaft

(dirt, damage of

camshaft)

3 CHECK CURRENT DATA.

1) Drive with acceleration and deceleration at

80 km/h (50 MPH) or less.

NOTE:

Drive to an extent that the duty output of oil flow

control solenoid valve increases.

2) Read the values of «OCV Duty R» and

«VVT Adv. Ang. Amount R» using the Subaru

Select Monitor.

NOTE:

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

When the value of «OCV Duty

R» increases more than 10%,

is the value of «VVT Adv. Ang.

Amount R» approx. 0 deg?

Check the follow-

ing item and repair

or replace if neces-

sary.

• Intake cam

sprocket (clog or

dirt of oil routing,

setting of spring)

• Intake camshaft

(dirt, damage of

camshaft)

Perform the follow-

ing procedures,

and clean the oil

routing.

Replace the

engine oil and idle

the engine for 5

minutes, and then

replace the oil filter

and engine oil.

<Ref. to LU(w/o

STI)-11,

REPLACEMENT,

Engine Oil.> <Ref.

to LU(w/o STI)-53,

Engine Oil Filter.>

15WRX_STI_US_EN.book 99 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-100

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

G: DTC P0013 B CAMSHAFT POSITION ACTUATOR CIRCUIT/OPEN (BANK 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-18, DTC P0013 B CAMSHAFT POSITION ACTUATOR

CIRCUIT/OPEN (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK OUTPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 23 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

ECM

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E3B22

B550

215

B220

E66E63

E63

223

EN-10795

E159

231

E66

SBF-7

232221 262524201918

587

10 11

B550

EXHAUST

OIL CONTROL

SOLENOID LH

EXHAUST

OIL CONTROL

SOLENOID RH

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 100 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-101

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

3 CHECK POWER SUPPLY TO THE EXHAUST

OIL CONTROL SOLENOID RH.

Measure the voltage between exhaust oil con-

trol solenoid RH connector and engine ground.

Connector & terminal

(E63) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID RH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

exhaust oil control solenoid RH.

3) Measure the resistance between exhaust oil

control solenoid RH connector and engine

ground.

Connector & terminal

(E63) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and exhaust oil

control solenoid

RH connector.

5 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID RH CON-

NECTOR.

Measure the resistance of harness between

ECM connector and exhaust oil control solenoid

RH.

Connector & terminal

(E159) No. 23 — (E63) No. 2:

Is the resistance less than 1 Ω? Go to step 6. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and exhaust oil

control solenoid

RH connector

• Poor contact of

coupling connector

6 CHECK EXHAUST OIL CONTROL SOLE-

NOID RH.

Measure the resistance between exhaust oil

control solenoid RH terminals.

Terminals

No. 1 — No. 2:

Is the resistance 6 — 12 Ω? Repair the poor

contact of exhaust

oil control solenoid

RH connector.

Replace the

exhaust oil control

solenoid RH. <Ref.

to FU(w/o STI)-

108, Oil Control

Solenoid.>

Step Check Yes No

15WRX_STI_US_EN.book 101 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-102

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

H: DTC P0014 EXHAUST AVCS SYSTEM 1 (RANGE/PERFORMANCE)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-19, DTC P0014 EXHAUST AVCS SYSTEM 1 (RANGE/

PERFORMANCE), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 IDENTIFYING FAULTY PART.

1) Perform the Clear Memory Mode. <Ref. to

EN(w/o STI)(diag)-61, Clear Memory Mode.>

2) Replace the defective oil control solenoid by

the other (RH or LH, intake side or exhaust side)

oil control solenoid.

3) Perform appropriate drive cycle test. <Ref.

to EN(w/o STI)(diag)-50, Drive Cycle.>

4) Make sure that the fault occurrence (DTC

and incorrect advancing) has shifted to the

other location.

Did the detected DTC shift to

the location where the oil con-

trol solenoid was replaced?

Replace the faulty

oil control sole-

noid.

Go to step 2.

2 CHECK CURRENT DATA.

1) Start the engine and let it idle.

2) Read the value of «Exh. VVT Retard Ang.

R» using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

Is the value of «Exh. VVT

Retard Ang. R» approx. 0 deg?

Go to step 3. Check the follow-

ing item and repair

or replace if neces-

sary.

• Exhaust cam

sprocket (clog or

dirt of oil routing,

setting of spring)

• Exhaust cam-

shaft (dirt, dam-

age of camshaft)

3 CHECK CURRENT DATA.

1) Drive with acceleration and deceleration at

80 km/h (50 MPH) or less.

NOTE:

Drive to an extent that the duty output of oil flow

control solenoid valve increases.

2) Read the values of «Exh. OCV Duty R» and

«Exh. VVT Retard Ang. R» using the Subaru

Select Monitor.

NOTE:

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

When the value of «Exh. OCV

Duty R» increases more than

10%, is the value of «Exh. VVT

Retard Ang. R» approx. 0 deg?

Check the follow-

ing item and repair

or replace if neces-

sary.

• Exhaust cam

sprocket (clog or

dirt of oil routing,

setting of spring)

• Exhaust cam-

shaft (dirt, dam-

age of camshaft)

Perform the follow-

ing procedures,

and clean the oil

routing.

Replace the

engine oil and idle

the engine for 5

minutes, and then

replace the oil filter

and engine oil.

<Ref. to LU(w/o

STI)-11,

REPLACEMENT,

Engine Oil.> <Ref.

to LU(w/o STI)-53,

Engine Oil Filter.>

15WRX_STI_US_EN.book 102 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-103

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

I: DTC P0016 CRANKSHAFT POSITION - CAMSHAFT POSITION CORRELA-

TION (BANK1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-20, DTC P0016 CRANKSHAFT POSITION - CAM-

SHAFT POSITION CORRELATION (BANK1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is DTC other than P0016,

P0017, P0018 or P0019 dis-

played?

Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK INTAKE OIL CONTROL SOLENOID

RH.

Check the intake oil control solenoid RH. <Ref.

to FU(w/o STI)-110, INSPECTION, Oil Control

Solenoid.>

Is the intake oil control solenoid

RH normal?

Go to step 3. Replace the intake

oil control solenoid

RH. <Ref. to FU(w/

o STI)-108, Oil

Control Solenoid.>

3 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Using ST and by turning the crankshaft, align

the alignment marks of crank sprocket, intake

cam sprocket and exhaust cam sprocket. <Ref.

to ME(w/o STI)-116, Timing Chain Assembly.>

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain installed in

the proper position?

Go to step 4. Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

4 CHECK CAM CARRIER FILTER.

Check the filter installed to the cam carrier.

<Ref. to ME(w/o STI)-209, INSPECTION, Cam

Carrier.>

Is the cam carrier filter normal? Replace the intake

cam sprocket RH.

<Ref. to ME(w/o

STI)-141, Cam

Sprocket.> After

the operation is

complete, go to the

next step. Go to

step 5.

Replace the cam

carrier filter. <Ref.

to ME(w/o STI)-

172, Cam Carrier.>

15WRX_STI_US_EN.book 103 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-104

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

5 CHECK CURRENT DATA.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, OPERATION, Clear Memory

Mode.>

2) Start the engine and warm up completely.

3) Using the Subaru Select Monitor, read the

values of «VVT Initial Position Learning Value

#1» and «VVT Adv. Ang. Amount R» while the

vehicle is in stable condition for 30 seconds or

more with the engine idling.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

4) Calculate the values using the following for-

mula. Ignore the unit at this time.

|«VVT Initial Position Learning Value #1» – (60

+ «VVT Adv. Ang. Amount R»)|

Is the calculation result less

than 10?

Go to step 6. Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

6 CHECK DTC.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, OPERATION, Clear Memory

Mode.>

2) Perform drive cycle N. <Ref. to EN(w/o

STI)(diag)-59, DRIVE CYCLE N, PROCE-

DURE, Drive Cycle.>

Is the same DTC as current

diagnosis output?

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

End.

Step Check Yes No

15WRX_STI_US_EN.book 104 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-105

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

J: DTC P0017 CRANK AND CAM TIMING B SYSTEM FAILURE (BANK 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-21, DTC P0017 CRANK AND CAM TIMING B SYSTEM

FAILURE (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is DTC other than P0016,

P0017, P0018 or P0019 dis-

played?

Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK EXHAUST OIL CONTROL SOLE-

NOID RH.

Check the exhaust oil control solenoid RH.

<Ref. to FU(w/o STI)-110, INSPECTION, Oil

Control Solenoid.>

Is the exhaust oil control sole-

noid RH normal?

Go to step 3. Replace the

exhaust oil control

solenoid RH. <Ref.

to FU(w/o STI)-

108, Oil Control

Solenoid.>

3 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Using ST and by turning the crankshaft, align

the alignment marks of crank sprocket, intake

cam sprocket and exhaust cam sprocket. <Ref.

to ME(w/o STI)-116, Timing Chain Assembly.>

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain installed in

the proper position?

Go to step 4. Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

4 CHECK CAM CARRIER FILTER.

Check the filter installed to the cam carrier.

<Ref. to ME(w/o STI)-209, INSPECTION, Cam

Carrier.>

Is the cam carrier filter normal? Replace the

exhaust cam

sprocket RH. <Ref.

to ME(w/o STI)-

141, Cam

Sprocket.> After

the operation is

complete, go to the

next step. Go to

step 5.

Replace the cam

carrier filter. <Ref.

to ME(w/o STI)-

172, Cam Carrier.>

15WRX_STI_US_EN.book 105 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-106

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

5 CHECK CURRENT DATA.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, OPERATION, Clear Memory

Mode.>

2) Start the engine and warm up completely.

3) Using the Subaru Select Monitor, read the

values of «VVT Ex Initial Position Learning

Value #1» and «Exh. VVT Retard Ang. R» while

the vehicle is in stable condition for 30 seconds

or more with the engine idling.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

4) Calculate the values using the following for-

mula. Ignore the unit at this time.

|«VVT Ex Initial Position Learning Value #1» –

(90 – «Exh. VVT Retard Ang. R»)|

Is the calculation result less

than 10?

Go to step 6. Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

6 CHECK DTC.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, OPERATION, Clear Memory

Mode.>

2) Perform drive cycle N. <Ref. to EN(w/o

STI)(diag)-59, DRIVE CYCLE N, PROCE-

DURE, Drive Cycle.>

Is the same DTC as current

diagnosis output?

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

End.

Step Check Yes No

15WRX_STI_US_EN.book 106 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-107

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

K: DTC P0018 CRANKSHAFT POSITION - CAMSHAFT POSITION CORRELA-

TION (BANK2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-22, DTC P0018 CRANKSHAFT POSITION - CAM-

SHAFT POSITION CORRELATION (BANK2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is DTC other than P0016,

P0017, P0018 or P0019 dis-

played?

Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK INTAKE OIL CONTROL SOLENOID

LH.

Check the intake oil control solenoid LH. <Ref.

to FU(w/o STI)-110, INSPECTION, Oil Control

Solenoid.>

Is the intake oil control solenoid

LH normal?

Go to step 3. Replace the intake

oil control solenoid

LH. <Ref. to FU(w/

o STI)-108, Oil

Control Solenoid.>

3 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Using ST and by turning the crankshaft, align

the alignment marks of crank sprocket, intake

cam sprocket and exhaust cam sprocket. <Ref.

to ME(w/o STI)-116, Timing Chain Assembly.>

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain installed in

the proper position?

Go to step 4. Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

4 CHECK CAM CARRIER FILTER.

Check the filter installed to the cam carrier.

<Ref. to ME(w/o STI)-209, INSPECTION, Cam

Carrier.>

Is the cam carrier filter normal? Replace the intake

cam sprocket LH.

<Ref. to ME(w/o

STI)-141, Cam

Sprocket.> After

the operation is

complete, go to the

next step. Go to

step 5.

Replace the cam

carrier filter. <Ref.

to ME(w/o STI)-

172, Cam Carrier.>

15WRX_STI_US_EN.book 107 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-108

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

5 CHECK CURRENT DATA.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, OPERATION, Clear Memory

Mode.>

2) Start the engine and warm up completely.

3) Using the Subaru Select Monitor, read the

values of «VVT Initial Position Learning Value

#2» and «VVT Adv. Ang. Amount L» while the

vehicle is in stable condition for 30 seconds or

more with the engine idling.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

4) Calculate the values using the following for-

mula. Ignore the unit at this time.

|«VVT Initial Position Learning Value #2» – (60

+ «VVT Adv. Ang. Amount L»)|

Is the calculation result less

than 10?

Go to step 6. Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

6 CHECK DTC.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, OPERATION, Clear Memory

Mode.>

2) Perform drive cycle N. <Ref. to EN(w/o

STI)(diag)-59, DRIVE CYCLE N, PROCE-

DURE, Drive Cycle.>

Is the same DTC as current

diagnosis output?

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

End.

Step Check Yes No

15WRX_STI_US_EN.book 108 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-109

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

L: DTC P0019 CRANK AND CAM TIMING B SYSTEM FAILURE (BANK 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-22, DTC P0019 CRANK AND CAM TIMING B SYSTEM

FAILURE (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is DTC other than P0016,

P0017, P0018 or P0019 dis-

played?

Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK EXHAUST OIL CONTROL SOLE-

NOID LH.

Check the exhaust oil control solenoid LH.

<Ref. to FU(w/o STI)-110, INSPECTION, Oil

Control Solenoid.>

Is the exhaust oil control sole-

noid LH normal?

Go to step 3. Replace the

exhaust oil control

solenoid LH. <Ref.

to FU(w/o STI)-

108, Oil Control

Solenoid.>

3 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Using ST and by turning the crankshaft, align

the alignment marks of crank sprocket, intake

cam sprocket and exhaust cam sprocket. <Ref.

to ME(w/o STI)-116, Timing Chain Assembly.>

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain installed in

the proper position?

Go to step 4. Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

4 CHECK CAM CARRIER FILTER.

Check the filter installed to the cam carrier.

<Ref. to ME(w/o STI)-209, INSPECTION, Cam

Carrier.>

Is the cam carrier filter normal? Replace the

exhaust cam

sprocket LH. <Ref.

to ME(w/o STI)-

141, Cam

Sprocket.> After

the operation is

complete, go to the

next step. Go to

step 5.

Replace the cam

carrier filter. <Ref.

to ME(w/o STI)-

172, Cam Carrier.>

15WRX_STI_US_EN.book 109 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-110

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

5 CHECK CURRENT DATA.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, OPERATION, Clear Memory

Mode.>

2) Start the engine and warm up completely.

3) Using the Subaru Select Monitor, read the

values of «VVT Ex Initial Position Learning

Value #2» and «Exh. VVT Retard Ang. L» while

the vehicle is in stable condition for 30 seconds

or more with the engine idling.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

4) Calculate the values using the following for-

mula. Ignore the unit at this time.

|«VVT Ex Initial Position Learning Value #2» –

(90 – «Exh. VVT Retard Ang. L»)|

Is the calculation result less

than 10?

Go to step 6. Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

6 CHECK DTC.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, OPERATION, Clear Memory

Mode.>

2) Perform drive cycle N. <Ref. to EN(w/o

STI)(diag)-59, DRIVE CYCLE N, PROCE-

DURE, Drive Cycle.>

Is the same DTC as current

diagnosis output?

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

End.

Step Check Yes No

15WRX_STI_US_EN.book 110 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-111

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

M: DTC P0020 "A" CAMSHAFT POSITION ACTUATOR CIRCUIT/OPEN (BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-22, DTC P0020 "A" CAMSHAFT POSITION ACTUA-

TOR CIRCUIT/OPEN (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK OUTPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 15 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E3B22

B550

215

B220

E38E37

E38

EN-10796

E159

215

E37

SBF-7

ECM

232221 262524201918

587

10 11

B550

INTAKE

OIL CONTROL

SOLENOID LH

INTAKE

OIL CONTROL

SOLENOID RH

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 111 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-112

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

3 CHECK POWER SUPPLY TO THE INTAKE

OIL CONTROL SOLENOID LH.

Measure the voltage between intake oil control

solenoid LH connector and engine ground.

Connector & terminal

(E37) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID LH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

intake oil control solenoid LH.

3) Measure the resistance between intake oil

control solenoid LH connector and engine

ground.

Connector & terminal

(E37) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and intake oil con-

trol solenoid LH

connector.

5 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID LH CON-

NECTOR.

Measure the resistance of harness between

ECM connector and intake oil control solenoid

LH.

Connector & terminal

(E159) No. 15 — (E37) No. 2:

Is the resistance less than 1 Ω? Go to step 6. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and intake oil con-

trol solenoid LH

connector

• Poor contact of

coupling connector

6 CHECK INTAKE OIL CONTROL SOLENOID

LH.

Measure the resistance between intake oil con-

trol solenoid LH terminals.

Terminals

No. 1 — No. 2:

Is the resistance 6 — 12 Ω? Repair the poor

contact of intake oil

control solenoid

LH connector.

Replace the intake

oil control solenoid

LH. <Ref. to FU(w/

o STI)-108, Oil

Control Solenoid.>

Step Check Yes No

15WRX_STI_US_EN.book 112 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-113

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

N: DTC P0021 INTAKE CAMSHAFT POSITION - TIMING OVER-ADVANCED OR

SYSTEM PERFORMANCE (BANK 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-22, DTC P0021 INTAKE CAMSHAFT POSITION - TIM-

ING OVER-ADVANCED OR SYSTEM PERFORMANCE (BANK 2), Diagnostic Trouble Code (DTC) Detect-

ing Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 IDENTIFYING FAULTY PART.

1) Perform the Clear Memory Mode. <Ref. to

EN(w/o STI)(diag)-61, Clear Memory Mode.>

2) Replace the defective oil control solenoid by

the other (RH or LH, intake side or exhaust side)

oil control solenoid.

3) Perform appropriate drive cycle test. <Ref.

to EN(w/o STI)(diag)-50, Drive Cycle.>

4) Make sure that the fault occurrence (DTC

and incorrect advancing) has shifted to the

other location.

Did the detected DTC shift to

the location where the oil con-

trol solenoid was replaced?

Replace the faulty

oil control sole-

noid.

Go to step 2.

2 CHECK CURRENT DATA.

1) Start the engine and let it idle.

2) Read the value of «VVT Adv. Ang. Amount

L» using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

Is the value of «VVT Adv. Ang.

Amount L» approx. 0 deg?

Go to step 3. Check the follow-

ing item and repair

or replace if neces-

sary.

• Intake cam

sprocket (clog or

dirt of oil routing,

setting of spring)

• Intake camshaft

(dirt, damage of

camshaft)

3 CHECK CURRENT DATA.

1) Drive with acceleration and deceleration at

80 km/h (50 MPH) or less.

NOTE:

Drive to an extent that the duty output of oil flow

control solenoid valve increases.

2) Read the values of «OCV Duty L» and «VVT

Adv. Ang. Amount L» using the Subaru Select

Monitor.

NOTE:

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

When the value of «OCV Duty

L» increases more than 10%, is

the value of «VVT Adv. Ang.

Amount L» approx. 0 deg?

Check the follow-

ing item and repair

or replace if neces-

sary.

• Intake cam

sprocket (clog or

dirt of oil routing,

setting of spring)

• Intake camshaft

(dirt, damage of

camshaft)

Perform the follow-

ing procedures,

and clean the oil

routing.

Replace the

engine oil and idle

the engine for 5

minutes, and then

replace the oil filter

and engine oil.

<Ref. to LU(w/o

STI)-11,

REPLACEMENT,

Engine Oil.> <Ref.

to LU(w/o STI)-53,

Engine Oil Filter.>

15WRX_STI_US_EN.book 113 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-114

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

O: DTC P0023 B CAMSHAFT POSITION ACTUATOR CIRCUIT/OPEN (BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-22, DTC P0023 B CAMSHAFT POSITION ACTUATOR

CIRCUIT/OPEN (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK OUTPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 31 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

ECM

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E3B22

B550

215

B220

E66E63

E63

223

EN-10795

E159

231

E66

SBF-7

232221 262524201918

587

10 11

B550

EXHAUST

OIL CONTROL

SOLENOID LH

EXHAUST

OIL CONTROL

SOLENOID RH

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 114 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-115

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

3 CHECK POWER SUPPLY TO THE EXHAUST

OIL CONTROL SOLENOID LH.

Measure the voltage between exhaust oil con-

trol solenoid LH connector and engine ground.

Connector & terminal

(E66) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID LH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

exhaust oil control solenoid LH.

3) Measure the resistance between exhaust oil

control solenoid LH connector and engine

ground.

Connector & terminal

(E66) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and exhaust oil

control solenoid

LH connector.

5 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID LH CON-

NECTOR.

Measure the resistance of harness between

ECM connector and exhaust oil control solenoid

LH.

Connector & terminal

(E159) No. 31 — (E66) No. 2:

Is the resistance less than 1 Ω? Go to step 6. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and exhaust oil

control solenoid

LH connector

• Poor contact of

coupling connector

6 CHECK EXHAUST OIL CONTROL SOLE-

NOID LH.

Measure the resistance between exhaust oil

control solenoid LH terminals.

Terminals

No. 1 — No. 2:

Is the resistance 6 — 12 Ω? Repair the poor

contact of exhaust

oil control solenoid

LH connector.

Replace the

exhaust oil control

solenoid LH. <Ref.

to FU(w/o STI)-

108, Oil Control

Solenoid.>

Step Check Yes No

15WRX_STI_US_EN.book 115 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-116

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

P: DTC P0024 EXHAUST AVCS SYSTEM 2 (RANGE/PERFORMANCE)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-22, DTC P0024 EXHAUST AVCS SYSTEM 2 (RANGE/

PERFORMANCE), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 IDENTIFYING FAULTY PART.

1) Perform the Clear Memory Mode. <Ref. to

EN(w/o STI)(diag)-61, Clear Memory Mode.>

2) Replace the defective oil control solenoid by

the other (RH or LH, intake side or exhaust side)

oil control solenoid.

3) Perform appropriate drive cycle test. <Ref.

to EN(w/o STI)(diag)-50, Drive Cycle.>

4) Make sure that the fault occurrence (DTC

and incorrect advancing) has shifted to the

other location.

Did the detected DTC shift to

the location where the oil con-

trol solenoid was replaced?

Replace the faulty

oil control sole-

noid.

Go to step 2.

2 CHECK CURRENT DATA.

1) Start the engine and let it idle.

2) Read the value of «Exh. VVT Retard Ang.

L» using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

Is the value of «Exh. VVT

Retard Ang. L» approx. 0 deg?

Go to step 3. Check the follow-

ing item and repair

or replace if neces-

sary.

• Exhaust cam

sprocket (clog or

dirt of oil routing,

setting of spring)

• Exhaust cam-

shaft (dirt, dam-

age of camshaft)

3 CHECK CURRENT DATA.

1) Drive with acceleration and deceleration at

80 km/h (50 MPH) or less.

NOTE:

Drive to an extent that the duty output of oil flow

control solenoid valve increases.

2) Read the values of «Exh. OCV Duty L» and

«Exh. VVT Retard Ang. L» using the Subaru

Select Monitor.

NOTE:

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

When the value of «Exh. OCV

Duty L» increases more than

10%, is the value of «Exh. VVT

Retard Ang. L» approx. 0 deg?

Check the follow-

ing item and repair

or replace if neces-

sary.

• Exhaust cam

sprocket (clog or

dirt of oil routing,

setting of spring)

• Exhaust cam-

shaft (dirt, dam-

age of camshaft)

Perform the follow-

ing procedures,

and clean the oil

routing.

Replace the

engine oil and idle

the engine for 5

minutes, and then

replace the oil filter

and engine oil.

<Ref. to LU(w/o

STI)-11,

REPLACEMENT,

Engine Oil.> <Ref.

to LU(w/o STI)-53,

Engine Oil Filter.>

15WRX_STI_US_EN.book 116 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-117

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Q: DTC P0030 HO2S HEATER CONTROL CIRCUIT (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-22, DTC P0030 HO2S HEATER CONTROL CIRCUIT

(BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 117 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-118

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Start and warm up the engine.

2) Turn the ignition switch to OFF.

3) Disconnect the connectors from ECM and

front oxygen (A/F) sensor.

4) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E159) No. 9 — (E24) No. 2:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

Is the resistance less than 1 Ω? Go to step 2. Repair the open

circuit of harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

2 CHECK FRONT OXYGEN (A/F) SENSOR.

Measure the resistance between front oxygen

(A/F) sensor terminals.

Terminals

No. 2 — No. 3:

Is the resistance 2 — 3 Ω? Go to step 3. Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

3 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and front oxygen

(A/F) sensor connector.

Is there poor contact of ECM or

front oxygen (A/F) sensor con-

nector?

Repair the poor

contact of ECM or

front oxygen (A/F)

sensor connector.

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

15WRX_STI_US_EN.book 118 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-119

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

R: DTC P0031 HO2S HEATER CONTROL CIRCUIT LOW (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-24, DTC P0031 HO2S HEATER CONTROL CIRCUIT

LOW (BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 119 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-120

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY TO FRONT OXY-

GEN (A/F) SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from front oxy-

gen (A/F) sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between front oxygen

(A/F) sensor connector and engine ground.

Connector & terminal

(E24) No. 3 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the power

supply line.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

A/F, oxygen sen-

sor relay and front

oxygen (A/F) sen-

sor connector

• Poor contact of

A/F, oxygen sen-

sor relay connector

• Poor contact of

coupling connector

• Malfunction of A/

F, oxygen sensor

relay

2 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and front oxygen (A/F) sensor connector.

Connector & terminal

(E24) No. 2 — (E159) No. 9:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

3 CHECK GROUND CIRCUIT FOR ECM.

Measure the resistance of harness between

ECM connector and engine ground.

Connector & terminal

(B134) No. 35 — Engine ground:

(B134) No. 47 — Engine ground:

(E159) No. 10 — Engine ground:

(E159) No. 17 — Engine ground:

(E159) No. 18 — Engine ground:

(E159) No. 25 — Engine ground:

(E159) No. 26 — Engine ground:

Is the resistance less than 5 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

coupling connector

4 CHECK FRONT OXYGEN (A/F) SENSOR.

Measure the resistance between front oxygen

(A/F) sensor terminals.

Terminals

No. 2 — No. 3:

Is the resistance 2 — 3 Ω? Repair the poor

contact of ECM

connector.

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

15WRX_STI_US_EN.book 120 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-121

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

S: DTC P0032 HO2S HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-25, DTC P0032 HO2S HEATER CONTROL CIRCUIT

HIGH (BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 121 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-122

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 9 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

Go to step 2.

2 CHECK GROUND CIRCUIT FOR ECM.

1) Disconnect the connector from ECM.

2) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 35 — Engine ground:

(B134) No. 47 — Engine ground:

(E159) No. 10 — Engine ground:

(E159) No. 17 — Engine ground:

(E159) No. 18 — Engine ground:

(E159) No. 25 — Engine ground:

(E159) No. 26 — Engine ground:

Is the resistance less than 5 Ω? Repair the poor

contact of ECM

connector.

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 122 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-123

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

T: DTC P0037 HO2S HEATER CONTROL CIRCUIT LOW (BANK 1 SENSOR 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-26, DTC P0037 HO2S HEATER CONTROL CIRCUIT

LOW (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 123 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-124

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY TO REAR OXY-

GEN SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from rear oxygen

sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between rear oxygen

sensor connector and engine ground.

Connector & terminal

(E25) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the power

supply line.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

A/F, oxygen sen-

sor relay and rear

oxygen sensor

connector

• Poor contact of

A/F, oxygen sen-

sor relay connector

• Poor contact of

coupling connector

• Malfunction of A/

F, oxygen sensor

relay

2 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and rear oxygen sensor connector.

Connector & terminal

(E25) No. 2 — (E159) No. 3:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

3 CHECK GROUND CIRCUIT FOR ECM.

Measure the resistance of harness between

ECM connector and engine ground.

Connector & terminal

(B134) No. 35 — Engine ground:

(B134) No. 47 — Engine ground:

(E159) No. 10 — Engine ground:

(E159) No. 17 — Engine ground:

(E159) No. 18 — Engine ground:

(E159) No. 25 — Engine ground:

(E159) No. 26 — Engine ground:

Is the resistance less than 5 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

coupling connector

4 CHECK REAR OXYGEN SENSOR.

Measure the resistance between rear oxygen

sensor connector terminals.

Terminals

No. 1 — No. 2:

Is the resistance 5 — 7 Ω? Repair the poor

contact of ECM

connector.

Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

15WRX_STI_US_EN.book 124 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-125

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

U: DTC P0038 HO2S HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-27, DTC P0038 HO2S HEATER CONTROL CIRCUIT

HIGH (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 125 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-126

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 3 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and rear

oxygen sensor

connector.

Go to step 2.

2 CHECK GROUND CIRCUIT FOR ECM.

1) Disconnect the connector from ECM.

2) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 35 — Engine ground:

(B134) No. 47 — Engine ground:

(E159) No. 10 — Engine ground:

(E159) No. 17 — Engine ground:

(E159) No. 18 — Engine ground:

(E159) No. 25 — Engine ground:

(E159) No. 26 — Engine ground:

Is the resistance less than 5 Ω? Repair the poor

contact of ECM

connector.

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 126 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-127

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

V: DTC P0068 MAP/MAF - THROTTLE POSITION CORRELATION

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-28, DTC P0068 MAP/MAF - THROTTLE POSITION

CORRELATION, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK AIR INTAKE SYSTEM. Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

Go to step 2.

2 CHECK MANIFOLD ABSOLUTE PRESSURE

AND INTAKE AIR TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Using the Subaru Select Monitor or a gen-

eral scan tool, read the value in «Mani. Absolute

Pressure».

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

“General Scan Tool Instruction Manual”.

Is the value in «Mani. Absolute

Pressure» 73.3 — 106.6 kPa

(550 — 800 mmHg, 21.65 —

31.50 inHg) when the ignition is

turned ON, and 20.0 — 46.7

kPa (150 — 350 mmHg, 5.91 —

13.78 inHg) during idling?

Go to step 3. Replace the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-120, Mani-

fold Absolute Pres-

sure and Intake Air

Temperature Sen-

sor.>

3 CHECK THROTTLE OPENING ANGLE.

Using the Subaru Select Monitor or a general

scan tool, read the value in «Throttle Opening

Angle».

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

“General Scan Tool Instruction Manual”.

Is the value in «Throttle Open-

ing Angle» with the throttle fully

closed less than 5%?

Go to step 4. Replace the elec-

tronic throttle con-

trol. <Ref. to FU(w/

o STI)-15, Throttle

Body.>

4 CHECK THROTTLE OPENING ANGLE. Is the value in «Throttle Open-

ing Angle» with the throttle fully

open 85% or more?

Replace the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-120, Mani-

fold Absolute Pres-

sure and Intake Air

Temperature Sen-

sor.>

Replace the elec-

tronic throttle con-

trol. <Ref. to FU(w/

o STI)-15, Throttle

Body.>

15WRX_STI_US_EN.book 127 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-128

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

W: DTC P0071 AMBIENT TEMPERATURE SENSOR CIRCUIT "A" RANGE/PER-

FORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-30, DTC P0071 AMBIENT TEMPERATURE SENSOR

CIRCUIT "A" RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK CURRENT DATA.

1) Turn the ignition switch to ON.

2) Read the value of «Ambient Air Tempera-

ture» using the Subaru Select Monitor or a gen-

eral scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For HVAC System”.

<Ref. to AC(diag)-40, Read Current Data.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

3) Read the change of the value in «Ambient

Air Temperature» while heating and cooling the

ambient sensor using a hair dryer.

CAUTION:

Do not heat the part to the temperature

where you cannot touch it with your bare

hand in order to prevent burning yourself

and protect the part.

Does the value of «Ambient Air

Temperature» change between

heating and cooling?

Repair the poor

contact of ECM

connector.

Replace the ambi-

ent sensor. <Ref.

to AC-72, Ambient

Sensor.>

15WRX_STI_US_EN.book 128 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-129

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

X: DTC P0072 AMBIENT TEMPERATURE SENSOR CIRCUIT "A" LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-32, DTC P0072 AMBIENT TEMPERATURE SENSOR

CIRCUIT "A" LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

Y: DTC P0073 AMBIENT TEMPERATURE SENSOR CIRCUIT "A" HIGH

NOTE:

For the diagnostic procedure, refer to DTC P0072. <Ref. to EN(w/o STI)(diag)-129, DTC P0072 AMBIENT

TEMPERATURE SENSOR CIRCUIT "A" LOW, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

Step Check Yes No

1 CHECK DTC.

Check for DTC. <Ref. to EN(w/o STI)(diag)-46,

Read Diagnostic Trouble Code (DTC).>

Is P0072 or P0073 displayed in

«Present fault»?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK COMBINATION METER.

Check the combination meter system. <Ref. to

IDI(diag)-2, Basic Diagnostic Procedure.>

Is the combination meter sys-

tem normal?

Repair the poor

contact of ECM

connector.

Repair the combi-

nation meter sys-

tem. <Ref. to

IDI(diag)-2, Basic

Diagnostic Proce-

dure.>

15WRX_STI_US_EN.book 129 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-130

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Z: DTC P0087 FUEL RAIL/SYSTEM PRESSURE - TOO LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-33, DTC P0087 FUEL RAIL/SYSTEM PRESSURE -

TOO LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Poor acceleration

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR FUEL DELIVERY LINE LEAK-

AGE.

Visually check the fuel delivery line for leakage.

WARNING:

• When checking fuel delivery line during

engine operation, be very careful so that

one's hair, body and clothes do not touch

the rotating part in the engine compartment.

• If there is fuel leakage, the fuel can be

combusted spontaneously by the engine

heat, resulting in serious accident. There-

fore, take extra care of possible fuel leak-

age.

• Prepare the necessary fire-extinguishing

appliance for immediate fire fighting in case

of fire.

NOTE:

Concerning the section where visible inspection

is difficult, the fuel odor provides a good indica-

tion of determining the fuel leakage.

Are there leaks from the fuel

delivery line?

Replace the faulty

fuel delivery line.

<Ref. to FU(w/o

STI)-194, Fuel

Delivery and Evap-

oration Lines.>

<Ref. to FU(w/o

STI)-51, Fuel

Injector.>

Go to step 2.

2 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 3.

3 CHECK EXPERIENCE OF RUNNING OUT OF

FUEL.

Check if there was an experience of running out

of fuel using “Check List for Interview”. <Ref. to

EN(w/o STI)(diag)-5, CHECK LIST NO. 2,

CHECK, Check List for Interview.>

Has the vehicle experienced

running out of fuel?

Finish the diagno-

sis.

NOTE:

DTC may be

stored by running

out of fuel.

Go to step 4.

15WRX_STI_US_EN.book 130 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-131

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

4 CHECK FUEL PRESSURE.

1) Start the engine.

2) Using the Subaru Select Monitor, read the

values in «Fuel Rail Pressure A» and «Com-

manded Fuel Rail Pressure A» when racing the

engine.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value in «Fuel Rail Pres-

sure A» synchronized with the

one in «Commanded Fuel Rail

Pressure A»?

Go to step 5. • The value in

«Fuel Rail Pres-

sure A» does not

increase: Go to

step 7.

• The value in

«Fuel Rail Pres-

sure A» does not

change: Replace

the fuel pressure

sensor. <Ref. to

FU(w/o STI)-71,

Fuel Pressure

Sensor.>

5 CHECK OF FUEL PUMP.

1) Turn the ignition switch to ON. (engine OFF)

2) From «Fuel Pump Control» of «System

Operation Check Mode», check the operating

sound of the fuel pump when performing «ON/

OFF drive» for the fuel pump.

NOTE:

For detailed operation procedures, refer to “PC

application help for Subaru Select Monitor”.

Does the fuel pump emit oper-

ating sound?

Go to step 6. Check fuel pump

circuit. <Ref. to

EN(w/o STI)(diag)-

82, FUEL PUMP

CIRCUIT, Diag-

nostics for Engine

Starting Failure.>

6 CHECK FUEL PRESSURE (LOW PRESSURE

SIDE).

Check the fuel pressure on low-pressure side.

<Ref. to ME(w/o STI)-31, INSPECTION, Fuel

Pressure.>

Is the fuel pressure normal? Go to step 7. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

7 CHECK FOR FUEL DELIVERY LINE LEAK-

AGE (HIGH PRESSURE SIDE).

1) Start the engine.

2) Using the Subaru Select Monitor, read the

change in value of «Fuel Rail Pressure A» when

stopping the engine.

NOTE:

• In order to maintain the communication with

Subaru Select Monitor, turn the ignition switch

to OFF, and immediately turn it to ON.

• For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Does the value of «Fuel Rail

Pressure A» decrease rapidly?

Go to step 8. Go to step 9.

8 CHECK HIGH-PRESSURE FUEL PUMP.

Check the high-pressure fuel pump. <Ref. to

FU(w/o STI)-82, INSPECTION, High Pressure

Fuel Pump.>

Is the high-pressure fuel pump

normal?

Go to step 9. Replace the high-

pressure fuel

pump. <Ref. to

FU(w/o STI)-74,

High Pressure

Fuel Pump.>

Step Check Yes No

15WRX_STI_US_EN.book 131 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-132

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

9 CHECK FOR REPRODUCTION OF FAILURE.

1) Perform the Clear Memory Mode. <Ref. to

EN(w/o STI)(diag)-61, Clear Memory Mode.>

2) Perform appropriate drive cycle test. <Ref.

to EN(w/o STI)(diag)-50, Drive Cycle.>

3) Read the DTC. <Ref. to EN(w/o STI)(diag)-

46, Read Diagnostic Trouble Code (DTC).>

Is the same DTC as current

diagnosis output?

Replace the high-

pressure fuel

pump. <Ref. to

FU(w/o STI)-74,

High Pressure

Fuel Pump.> After

replacement, go to

the next step. Go to

step 10.

NOTE:

When the high-

pressure fuel

pump has been re-

placed in step 8, go

to the next step

without replacing

the high-pressure

fuel pump. Go to

step 11.

End.

10 CHECK FOR REPRODUCTION OF FAILURE.

1) Perform the Clear Memory Mode. <Ref. to

EN(w/o STI)(diag)-61, Clear Memory Mode.>

2) Perform appropriate drive cycle test. <Ref.

to EN(w/o STI)(diag)-50, Drive Cycle.>

3) Read the DTC. <Ref. to EN(w/o STI)(diag)-

46, Read Diagnostic Trouble Code (DTC).>

Is the same DTC as current

diagnosis output?

Go to step 11.End.

11 CHECK FOR FUEL DELIVERY LINE LEAK-

AGE (HIGH PRESSURE SIDE).

1) Start the engine.

2) Using the Subaru Select Monitor, read the

change in value of «Fuel Rail Pressure A» when

stopping the engine.

NOTE:

• In order to maintain the communication with

Subaru Select Monitor, turn the ignition switch

to OFF, and immediately turn it to ON.

• For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Does the value of «Fuel Rail

Pressure A» decrease rapidly?

Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

Repair the poor

contact of ECM

connector.

Step Check Yes No

15WRX_STI_US_EN.book 132 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-133

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AA:DTC P0088 FUEL RAIL/SYSTEM PRESSURE - TOO HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-34, DTC P0088 FUEL RAIL/SYSTEM PRESSURE -

TOO HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Poor driving performance

• Poor acceleration

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK FUEL PRESSURE.

1) Start the engine.

2) Using Subaru Select Monitor, read the val-

ues in «Fuel Rail Pressure A» and «Com-

manded Fuel Rail Pressure A» until the vehicle

is accelerated to 60 km/h (37.3 MPH) from the

parked state and stops again.

CAUTION:

• Follow traffic rules and give the highest

priority to safe driving.

• During driving, do not operate or gaze at

the Subaru Select Monitor.

• Always check the measurement value af-

ter bringing the vehicle to a stop in a safe

place.

NOTE:

• In order to apply the running load to the vehi-

cle, actually drive the vehicle, and read the

measurement value.

• For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value in «Fuel Rail Pres-

sure A» synchronized with the

one in «Commanded Fuel Rail

Pressure A»?

Replace the high-

pressure fuel

pump. <Ref. to

FU(w/o STI)-74,

High Pressure

Fuel Pump.> After

replacement, go to

the next step. Go to

step 3.

Replace the fuel

pressure sensor.

<Ref. to FU(w/o

STI)-71, Fuel Pres-

sure Sensor.>

3 CHECK FOR REPRODUCTION OF FAILURE.

1) Perform the Clear Memory Mode. <Ref. to

EN(w/o STI)(diag)-61, Clear Memory Mode.>

2) Perform appropriate drive cycle test. <Ref.

to EN(w/o STI)(diag)-50, Drive Cycle.>

3) Read the DTC. <Ref. to EN(w/o STI)(diag)-

46, Read Diagnostic Trouble Code (DTC).>

Is the same DTC as current

diagnosis output?

Repair the poor

contact of ECM

connector.

End.

15WRX_STI_US_EN.book 133 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-134

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AB:DTC P0096 INTAKE AIR TEMPERATURE SENSOR #2 RANGE/PERFOR-

MANCE PROBLEM

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-35, DTC P0096 INTAKE AIR TEMPERATURE SENSOR

#2 RANGE/PERFORMANCE PROBLEM, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK CURRENT DATA.

1) Turn the ignition switch to ON.

2) Read the value of «IAT Sensor #12» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

3) Read the change of the value in «IAT Sen-

sor #12» while heating and cooling the manifold

absolute pressure and intake air temperature

sensor using a hair dryer.

CAUTION:

Do not heat the part to the temperature

where you cannot touch it with your bare

hand in order to prevent burning yourself

and protect the part.

Does the value of «IAT Sensor

#12» change between heating

and cooling?

Repair the poor

contact of ECM

connector.

Replace the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-120, Mani-

fold Absolute Pres-

sure and Intake Air

Temperature Sen-

sor.>

15WRX_STI_US_EN.book 134 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-135

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AC:DTC P0097 INTAKE AIR TEMPERATURE SENSOR #2 CIRCUIT (LOW)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-37, DTC P0097 INTAKE AIR TEMPERATURE SENSOR

#2 CIRCUIT (LOW), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

E159C:

E124

B25

C27

EN-10320

1234

E124

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

4C19

ECM

(GRAY)

(BLACK)

MANIFOLD ABSOLUTE PRESSURE &

INTAKE AIR TEMPERATURE SENSOR

15WRX_STI_US_EN.book 135 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-136

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «IAT Sensor #12» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value in «IAT Sensor

#12» 120°C (248°F) or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND

MANIFOLD ABSOLUTE PRESSURE AND IN-

TAKE AIR TEMPERATURE SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the manifold absolute pressure and intake air

temperature sensor.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 25 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-120, Mani-

fold Absolute Pres-

sure and Intake Air

Temperature Sen-

sor.>

Repair the ground

short circuit of har-

ness between

ECM connector

and the manifold

absolute pressure

and intake air tem-

perature sensor

connector.

15WRX_STI_US_EN.book 136 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-137

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AD:DTC P0098 INTAKE AIR TEMPERATURE SENSOR #2 CIRCUIT (HIGH)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-38, DTC P0098 INTAKE AIR TEMPERATURE SENSOR

#2 CIRCUIT (HIGH), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

E159C:

E124

B25

C27

EN-10320

1234

E124

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

4C19

ECM

(GRAY)

(BLACK)

MANIFOLD ABSOLUTE PRESSURE &

INTAKE AIR TEMPERATURE SENSOR

15WRX_STI_US_EN.book 137 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-138

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «IAT Sensor #12» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value in «IAT Sensor

#12» less than –40°C (–40°F)?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and manifold

absolute pressure and intake air temperature

sensor connector.

Is there poor contact of ECM or

manifold absolute pressure and

intake air temperature sensor

connector?

Repair the poor

contact of ECM or

manifold absolute

pressure and

intake air tempera-

ture sensor con-

nector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

MANIFOLD ABSOLUTE PRESSURE AND IN-

TAKE AIR TEMPERATURE SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the manifold absolute pressure and intake air

temperature sensor.

3) Measure the resistance of harness between

ECM connector and the manifold absolute pres-

sure and intake air temperature sensor connec-

tor.

Connector & terminal

(E158) No. 25 — (E124) No. 1:

(E159) No. 27 — (E124) No. 2:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit of the har-

ness between the

ECM connector

and the manifold

absolute pressure

& intake air tem-

perature sensor

connector.

4 CHECK HARNESS BETWEEN ECM AND

MANIFOLD ABSOLUTE PRESSURE AND IN-

TAKE AIR TEMPERATURE SENSOR CON-

NECTOR.

1) Connect all connectors.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E158) No. 25 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

harness between

ECM connector

and the manifold

absolute pressure

and intake air tem-

perature sensor

connector.

Replace the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-120, Mani-

fold Absolute Pres-

sure and Intake Air

Temperature Sen-

sor.>

15WRX_STI_US_EN.book 138 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-139

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AE:DTC P0101 MASS OR VOLUME AIR FLOW CIRCUIT RANGE/PERFOR-

MANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-39, DTC P0101 MASS OR VOLUME AIR FLOW CIR-

CUIT RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

15WRX_STI_US_EN.book 139 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-140

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AF:DTC P0102 MASS OR VOLUME AIR FLOW CIRCUIT LOW INPUT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-41, DTC P0102 MASS OR VOLUME AIR FLOW CIR-

CUIT LOW INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E3 B22

B122

EN-10799

123

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B122

J/C

B550

215

B220

B134A:

E158B:

A19

A16

A28

SBF-7

ECM

232221 262524201918

587

10 11

B550

: TERMINAL No. OPTIONAL

ARRANGEMENT

MAIN RELAY

BATTERY

FUSE HOLDER

MASS AIR FLOW &

INTAKE AIR TEMPERATURE SENSOR

(BROWN)

(BLACK)

15WRX_STI_US_EN.book 140 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-141

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Air Flow Sensor Volt-

age» using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «Air Flow Sensor

Voltage» less than 0.2 V?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK POWER SUPPLY OF MASS AIR

FLOW AND INTAKE AIR TEMPERATURE

SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the mass

air flow and intake air temperature sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between mass air flow

and intake air temperature sensor connector

and engine ground.

Connector & terminal

(B3) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

main relay and

mass air flow and

intake air tempera-

ture sensor con-

nector

• Poor contact of

main relay connec-

tor

3 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and the mass air flow and

intake air temperature sensor connector.

Connector & terminal

(B134) No. 16 — (B3) No. 3:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit of harness

between ECM con-

nector and the

mass air flow and

intake air tempera-

ture sensor con-

nector.

4 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(B134) No. 16 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the ground

short circuit of har-

ness between

ECM connector

and the mass air

flow and intake air

temperature sen-

sor connector.

5 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and mass air

flow and intake air temperature sensor connec-

tor.

Is there poor contact of ECM or

mass air flow and intake air

temperature sensor connector?

Repair the poor

contact of ECM or

mass air flow and

intake air tempera-

ture sensor con-

nector.

Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

15WRX_STI_US_EN.book 141 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-142

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AG:DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-42, DTC P0103 MASS OR VOLUME AIR FLOW CIR-

CUIT HIGH INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E3 B22

B122

EN-10799

123

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B122

J/C

B550

215

B220

B134A:

E158B:

A19

A16

A28

SBF-7

ECM

232221 262524201918

587

10 11

B550

: TERMINAL No. OPTIONAL

ARRANGEMENT

MAIN RELAY

BATTERY

FUSE HOLDER

MASS AIR FLOW &

INTAKE AIR TEMPERATURE SENSOR

(BROWN)

(BLACK)

15WRX_STI_US_EN.book 142 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-143

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Air Flow Sensor Volt-

age» using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «Air Flow Sensor

Voltage» 5 V or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the mass

air flow and intake air temperature sensor.

3) Start the engine.

4) Read the value of «Air Flow Sensor Volt-

age» using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «Air Flow Sensor

Voltage» 5 V or more?

Repair the short

circuit of harness

to power supply

between ECM con-

nector and the

mass air flow and

intake air tempera-

ture sensor con-

nector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Measure the resistance of harness between

mass air flow and intake air temperature sensor

connector and engine ground.

Connector & terminal

(B3) No. 2 — Engine ground:

Is the resistance less than 5 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and the mass air

flow and intake air

temperature sen-

sor connector

• Poor contact of

ECM connector

4 CHECK FOR POOR CONTACT.

Check for poor contact of mass air flow and

intake air temperature sensor connector.

Is there poor contact of mass

air flow and intake air tempera-

ture sensor connector?

Repair the poor

contact of mass air

flow and intake air

temperature sen-

sor connector.

Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

15WRX_STI_US_EN.book 143 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-144

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AH:DTC P0107 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE

CIRCUIT LOW INPUT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-43, DTC P0107 MANIFOLD ABSOLUTE PRESSURE/

BAROMETRIC PRESSURE CIRCUIT LOW INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

E159C:

E124

B25

C27

EN-10320

1234

E124

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

4C19

ECM

(GRAY)

(BLACK)

MANIFOLD ABSOLUTE PRESSURE &

INTAKE AIR TEMPERATURE SENSOR

15WRX_STI_US_EN.book 144 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-145

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Mani. Absolute Pres-

sure» using the Subaru Select Monitor or a gen-

eral scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Mani. Absolute

Pressure» less than 13.3 kPa

(100 mmHg, 3.94 inHg)?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK POWER SUPPLY OF MANIFOLD

ABSOLUTE PRESSURE AND INTAKE AIR

TEMPERATURE SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the manifold

absolute pressure and intake air temperature

sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between the manifold

absolute pressure and intake air temperature

sensor connector and engine ground.

Connector & terminal

(E124) No. 4 (+) — Engine ground (–):

Is the voltage 4.5 V or more? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and the manifold

absolute pressure

and intake air tem-

perature sensor

connector

• Poor contact of

ECM connector

3 CHECK HARNESS BETWEEN ECM AND

MANIFOLD ABSOLUTE PRESSURE AND IN-

TAKE AIR TEMPERATURE SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and the manifold absolute pres-

sure and intake air temperature sensor connec-

tor.

Connector & terminal

(E158) No. 4 — (E124) No. 3:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit in harness

between the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor connector.

4 CHECK HARNESS BETWEEN ECM AND

MANIFOLD ABSOLUTE PRESSURE AND IN-

TAKE AIR TEMPERATURE SENSOR CON-

NECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 4 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the ground

short circuit of har-

ness between

ECM connector

and the manifold

absolute pressure

and intake air tem-

perature sensor

connector.

15WRX_STI_US_EN.book 145 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-146

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

5 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and manifold

absolute pressure and intake air temperature

sensor connector.

Is there poor contact of ECM or

manifold absolute pressure and

intake air temperature sensor

connector?

Repair the poor

contact of ECM or

manifold absolute

pressure and

intake air tempera-

ture sensor con-

nector.

Replace the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-120, Mani-

fold Absolute Pres-

sure and Intake Air

Temperature Sen-

sor.>

Step Check Yes No

15WRX_STI_US_EN.book 146 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-147

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AI: DTC P0108 MANIFOLD ABSOLUTE PRESSURE/BAROMETRIC PRESSURE

CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-44, DTC P0108 MANIFOLD ABSOLUTE PRESSURE/

BAROMETRIC PRESSURE CIRCUIT HIGH INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

E159C:

E124

B25

C27

EN-10320

1234

E124

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

4C19

ECM

(GRAY)

(BLACK)

MANIFOLD ABSOLUTE PRESSURE &

INTAKE AIR TEMPERATURE SENSOR

15WRX_STI_US_EN.book 147 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-148

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Mani. Absolute Pres-

sure» using the Subaru Select Monitor or a gen-

eral scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Mani. Absolute

Pressure» 256 kPa (1,920.2

mmHg, 75.6 inHg) or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND

MANIFOLD ABSOLUTE PRESSURE AND IN-

TAKE AIR TEMPERATURE SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the manifold

absolute pressure and intake air temperature

sensor.

3) Start the engine.

4) Read the value of «Mani. Absolute Pres-

sure» using the Subaru Select Monitor or a gen-

eral scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Mani. Absolute

Pressure» 256 kPa (1,920.2

mmHg, 75.6 inHg) or more?

Repair the short

circuit to power in

harness between

ECM connector

and the manifold

absolute pressure

and intake air tem-

perature sensor

connector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

MANIFOLD ABSOLUTE PRESSURE AND IN-

TAKE AIR TEMPERATURE SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Measure the resistance of harness between

manifold absolute pressure and intake air tem-

perature sensor connector and engine ground.

Connector & terminal

(E124) No. 2 — Engine ground:

Is the resistance less than 5 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and the manifold

absolute pressure

and intake air tem-

perature sensor

connector

• Poor contact of

ECM connector

15WRX_STI_US_EN.book 148 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-149

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

4 CHECK FOR POOR CONTACT.

Check for poor contact of the manifold absolute

pressure and intake air temperature sensor

connector.

Is there poor contact of the

manifold absolute pressure and

intake air temperature sensor

connector?

Repair the poor

contact of the man-

ifold absolute pres-

sure and intake air

temperature sen-

sor connector.

Replace the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-120, Mani-

fold Absolute Pres-

sure and Intake Air

Temperature Sen-

sor.>

Step Check Yes No

15WRX_STI_US_EN.book 149 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-150

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AJ:DTC P0111 INTAKE AIR TEMPERATURE SENSOR RANGE/PERFORMANCE

PROBLEM

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-45, DTC P0111 INTAKE AIR TEMPERATURE SENSOR

RANGE/PERFORMANCE PROBLEM, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK CURRENT DATA.

1) Turn the ignition switch to ON.

2) Read the value of «IAT Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

3) Read the change of the value in «IAT Sen-

sor #11» while heating and cooling the mass air

flow and intake air temperature sensor using a

hair dryer.

CAUTION:

Do not heat the part to the temperature

where you cannot touch it with your bare

hand in order to prevent burning yourself

and protect the part.

Does the value of «IAT Sensor

#11» change between heating

and cooling?

Repair the poor

contact of ECM

connector.

Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

15WRX_STI_US_EN.book 150 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-151

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AK:DTC P0112 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-48, DTC P0112 INTAKE AIR TEMPERATURE SENSOR

1 CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E3 B22

B122

EN-10799

123

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B122

J/C

B550

215

B220

B134A:

E158B:

A19

A16

A28

SBF-7

ECM

232221 262524201918

587

10 11

B550

: TERMINAL No. OPTIONAL

ARRANGEMENT

MAIN RELAY

BATTERY

FUSE HOLDER

MASS AIR FLOW &

INTAKE AIR TEMPERATURE SENSOR

(BROWN)

(BLACK)

15WRX_STI_US_EN.book 151 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-152

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «IAT Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value in «IAT Sensor

#11» 120°C (248°F) or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the mass air flow and intake air temperature

sensor.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 5 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

Repair the ground

short circuit of har-

ness between

ECM connector

and the mass air

flow and intake air

temperature sen-

sor connector.

15WRX_STI_US_EN.book 152 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-153

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AL:DTC P0113 INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-49, DTC P0113 INTAKE AIR TEMPERATURE SENSOR

1 CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E3 B22

B122

EN-10799

123

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B122

J/C

B550

215

B220

B134A:

E158B:

A19

A16

A28

SBF-7

ECM

232221 262524201918

587

10 11

B550

: TERMINAL No. OPTIONAL

ARRANGEMENT

MAIN RELAY

BATTERY

FUSE HOLDER

MASS AIR FLOW &

INTAKE AIR TEMPERATURE SENSOR

(BROWN)

(BLACK)

15WRX_STI_US_EN.book 153 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-154

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «IAT Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value in «IAT Sensor

#11» less than –40°C (–40°F)?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and mass air

flow and intake air temperature sensor connec-

tor.

Is there poor contact of ECM or

mass air flow and intake air

temperature sensor connector?

Repair the poor

contact of ECM or

mass air flow and

intake air tempera-

ture sensor con-

nector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the mass air flow and intake air temperature

sensor.

3) Measure the resistance of harness between

ECM connector and the mass air flow and

intake air temperature sensor connector.

Connector & terminal

(E158) No. 5 — (B3) No. 4:

(B134) No. 19 — (B3) No. 5:

Is the resistance less than 1 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and the mass air

flow and intake air

temperature sen-

sor connector

• Poor contact of

coupling connector

4 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Connect all connectors.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E158) No. 5 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit of harness

to power supply

between ECM con-

nector and the

mass air flow and

intake air tempera-

ture sensor con-

nector.

Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

15WRX_STI_US_EN.book 154 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-155

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AM:DTC P0116 ENGINE COOLANT TEMPERATURE SENSOR 1 CIRCUIT

RANGE/PERFORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-50, DTC P0116 ENGINE COOLANT TEMPERATURE

SENSOR 1 CIRCUIT RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Hard to start

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

1) Disconnect the connectors from the engine

coolant temperature sensor.

2) Measure the resistance between engine

coolant temperature sensor terminals when the

engine coolant is cold and after warmed up.

Terminals

No. 1 — No. 2:

Is the resistance of engine cool-

ant temperature sensor differ-

ent between when engine

coolant is cold and after

warmed up?

Repair the poor

contact of ECM

connector.

Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

15WRX_STI_US_EN.book 155 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-156

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AN:DTC P0117 ENGINE COOLANT TEMPERATURE CIRCUIT LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-52, DTC P0117 ENGINE COOLANT TEMPERATURE

CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Hard to start

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

E159C:

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

C27

B38

EN-10322

ECM

ENGINE COOLANT

TEMPERATURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 156 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-157

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Coolant Temp.» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Coolant Temp.»

150°C (302°F) or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

engine coolant temperature sensor.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 38 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

Repair the short

circuit to ground in

harness between

ECM connector

and engine coolant

temperature sen-

sor connector.

15WRX_STI_US_EN.book 157 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-158

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AO:DTC P0118 ENGINE COOLANT TEMPERATURE CIRCUIT HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-53, DTC P0118 ENGINE COOLANT TEMPERATURE

CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Hard to start

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

E159C:

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

C27

B38

EN-10322

ECM

ENGINE COOLANT

TEMPERATURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 158 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-159

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Coolant Temp.» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Coolant Temp.»

less than –40°C (–40°F)?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and engine cool-

ant temperature sensor connector.

Is there poor contact of ECM or

engine coolant temperature

sensor connector?

Repair the poor

contact of ECM or

engine coolant

temperature sen-

sor connector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

engine coolant temperature sensor.

3) Measure the resistance of harness between

ECM connector and engine coolant tempera-

ture sensor connector.

Connector & terminal

(E159) No. 27 — (E8) No. 1:

(E158) No. 38 — (E8) No. 2:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit of the har-

ness between the

ECM connector

and engine coolant

temperature sen-

sor connector.

4 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

1) Connect all connectors.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E158) No. 38 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit of harness

to power supply

between ECM con-

nector and engine

coolant tempera-

ture sensor con-

nector.

Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

15WRX_STI_US_EN.book 159 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-160

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AP:DTC P0122 THROTTLE/PEDAL POSITION SENSOR/SWITCH “A” CIRCUIT

LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-54, DTC P0122 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “A” CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 160 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-161

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

electronic throttle control.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 18 — Engine ground:

(E158) No. 17 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 2. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 161 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-162

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK SHORT CIRCUIT INSIDE THE ECM.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 1 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the elec-

tronic throttle con-

trol. <Ref. to FU(w/

o STI)-15, Throttle

Body.>

Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

Replace the ECM if

defective. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

Step Check Yes No

15WRX_STI_US_EN.book 162 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-163

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AQ:DTC P0123 THROTTLE/PEDAL POSITION SENSOR/SWITCH “A” CIRCUIT

HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-55, DTC P0123 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “A” CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 163 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-164

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

electronic throttle control.

3) Measure the resistance of harness between

ECM connector and electronic throttle control

connector.

Connector & terminal

(E158) No. 17 — (E57) No. 1:

(E158) No. 30 — (E57) No. 3:

Is the resistance less than 1 Ω? Go to step 2. Repair the open

circuit of harness

between ECM con-

nector and elec-

tronic throttle

control connector.

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 164 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-165

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 3 — Engine ground:

Is the resistance less than 5 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

ECM connector

• Poor contact of

coupling connector

3 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 1 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 17 — (E158) No. 18:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of elec-

tronic throttle con-

trol connector.

Replace the elec-

tronic throttle con-

trol if defective.

<Ref. to FU(w/o

STI)-15, Throttle

Body.>

Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Step Check Yes No

15WRX_STI_US_EN.book 165 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-166

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AR:DTC P0125 INSUFFICIENT COOLANT TEMPERATURE FOR CLOSED LOOP

FUEL CONTROL

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-56, DTC P0125 INSUFFICIENT COOLANT TEMPERA-

TURE FOR CLOSED LOOP FUEL CONTROL, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Engine does not return to idle.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK TIRE SIZE. Is the tire size as specified and

the same size as three other

wheels?

Go to step 2. Replace the tire.

2 CHECK ENGINE COOLANT.

Check the following items:

• Amount of engine coolant

• Engine coolant freeze

• Contamination of engine coolant

Is the engine coolant normal? Go to step 3. Fill or replace the

engine coolant.

<Ref. to CO(w/o

STI)-13,

REPLACEMENT,

Engine Coolant.>

3 CHECK THERMOSTAT. Does the thermostat remain

opened?

Replace the ther-

mostat. <Ref. to

CO(w/o STI)-33,

Thermostat.>

Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

15WRX_STI_US_EN.book 166 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-167

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AS:DTC P0128 COOLANT THERMOSTAT (ENGINE COOLANT TEMPERATURE

BELOW THERMOSTAT REGULATING TEMPERATURE)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-58, DTC P0128 COOLANT THERMOSTAT (ENGINE

COOLANT TEMPERATURE BELOW THERMOSTAT REGULATING TEMPERATURE), Diagnostic Trouble

Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Thermostat remains open.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK ENGINE COOLANT. Is the engine coolant amount

normal?

Go to step 3. Refill the engine

coolant. <Ref. to

CO(w/o STI)-13,

Engine Coolant.>

3 CHECK RADIATOR FAN.

1) Start the engine.

2) Check the radiator fan operation.

Does the radiator fan continu-

ously rotate for 3 minutes or

more during idling?

Repair radiator fan

circuit. <Ref. to

CO(w/o STI)-46,

Radiator Main Fan

and Fan Motor.>

<Ref. to CO(w/o

STI)-49, Radiator

Sub Fan and Fan

Motor.>

Replace the ther-

mostat. <Ref. to

CO(w/o STI)-33,

Thermostat.>

15WRX_STI_US_EN.book 167 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-168

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AT:DTC P0130 O2 SENSOR CIRCUIT (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-61, DTC P0130 O2 SENSOR CIRCUIT (BANK 1 SEN-

SOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 168 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-169

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FRONT OXYGEN (A/F) SENSOR DA-

TA.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) Idle the engine for one minute or more.

3) Read the value of «A/F Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «A/F Sensor

#11» 1.20 — 3.00 V?

Go to step 2. Go to step 3.

2 CHECK FRONT OXYGEN (A/F) SENSOR DA-

TA.

1) Race the engine so that the engine speed

reaches 3,000 rpm. (Five times in total)

2) Read the value of «A/F Sensor #11» at rac-

ing using the Subaru Select Monitor or a gen-

eral scan tool.

NOTE:

• To increase engine speed to 3,000 rpm, slow-

ly depress accelerator pedal for approximately

5 seconds, and quickly release accelerator ped-

al to decrease engine speed.

• Normally, the air fuel ratio is rich during rac-

ing.

Is the value of «A/F Sensor

#11» 2.5 V or more?

Go to step 5. Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

front oxygen (A/F) sensor.

3) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit of harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

4 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 15 — Engine ground:

(E158) No. 27 — Engine ground:

(E158) No. 39 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector.

15WRX_STI_US_EN.book 169 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-170

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

5 CHECK EXHAUST SYSTEM.

Check exhaust system parts.

NOTE:

Check the following items.

• Looseness and improper fitting of exhaust

system parts

• Damage (crack, hole etc.) of parts

• Looseness of front oxygen (A/F) sensor

• Loose part and improper installation between

front oxygen (A/F) sensor and rear oxygen sen-

sor

Is there any fault in exhaust

system?

Repair or replace

faulty parts.

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

Step Check Yes No

15WRX_STI_US_EN.book 170 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-171

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AU:DTC P0131 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-62, DTC P0131 O2 SENSOR CIRCUIT LOW VOLTAGE

(BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 171 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-172

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FRONT OXYGEN (A/F) SENSOR

CONNECTOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

front oxygen (A/F) sensor.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 15 — Engine ground:

(E158) No. 27 — Engine ground:

(E158) No. 39 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 3. Repair the short

circuit to ground in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector.

3 CHECK FOR POOR CONTACT.

Check for poor contact of the front oxygen (A/F)

sensor connector.

Is there poor contact of front

oxygen (A/F) sensor connec-

tor?

Repair the poor

contact of front

oxygen (A/F) sen-

sor connector.

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

15WRX_STI_US_EN.book 172 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-173

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AV:DTC P0132 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-63, DTC P0132 O2 SENSOR CIRCUIT HIGH VOLTAGE

(BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 173 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-174

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FRONT OXYGEN (A/F) SENSOR

CONNECTOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from front oxy-

gen (A/F) sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E158) No. 15 (+) — Engine ground (–):

(E158) No. 27 (+) — Engine ground (–):

(E158) No. 39 (+) — Engine ground (–):

Is the voltage 8 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

15WRX_STI_US_EN.book 174 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-175

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AW:DTC P0134 O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SEN-

SOR 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-64, DTC P0134 O2 SENSOR CIRCUIT NO ACTIVITY

DETECTED (BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 175 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-176

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

front oxygen (A/F) sensor.

3) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

Is the resistance less than 1 Ω? Go to step 2. Repair the open

circuit of harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and front oxygen

(A/F) sensor connector.

Is there poor contact of ECM or

front oxygen (A/F) sensor con-

nector?

Repair the poor

contact of ECM or

front oxygen (A/F)

sensor connector.

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

15WRX_STI_US_EN.book 176 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-177

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AX:DTC P0137 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-66, DTC P0137 O2 SENSOR CIRCUIT LOW VOLTAGE

(BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 177 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-178

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

keep the engine speed at 3,000 rpm. (2 minutes

maximum)

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.490 V or more?

Go to step 6. Go to step 2.

2 CHECK REAR OXYGEN SENSOR CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

4 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 16 — Engine ground

(E158) No. 42 — Engine ground

Is the resistance 1 Ω or more? Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and rear oxygen

sensor connector.

5 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between rear oxygen

sensor connector and engine ground.

Connector & terminal

(E25) No. 3 (+) — Engine ground (–):

Is the voltage 1.8 V or more? Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

6 CHECK EXHAUST SYSTEM.

Check exhaust system parts.

NOTE:

Check the following items.

• Looseness and improper fitting of exhaust

system parts

• Damage (crack, hole etc.) of parts

• Loose part and improper installation between

front oxygen (A/F) sensor and rear oxygen sen-

sor

Is there any fault in exhaust

system?

Repair or replace

faulty parts.

Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

15WRX_STI_US_EN.book 178 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-179

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AY:DTC P0138 O2 SENSOR CIRCUIT HIGH VOLTAGE (BANK 1 SENSOR 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-67, DTC P0138 O2 SENSOR CIRCUIT HIGH VOLTAGE

(BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 179 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-180

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

rapidly reduce the engine speed from 3,000

rpm.

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.250 V or less?

Go to step 5. Go to step 2.

2 CHECK REAR OXYGEN SENSOR CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

4 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between rear oxygen

sensor connector and engine ground.

Connector & terminal

(E25) No. 3 (+) — Engine ground (–):

Is the voltage 2.3 V or less? Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

5 CHECK EXHAUST SYSTEM.

Check exhaust system parts.

NOTE:

Check the following items.

• Looseness and improper fitting of exhaust

system parts

• Damage (crack, hole etc.) of parts

• Loose part and improper installation between

front oxygen (A/F) sensor and rear oxygen sen-

sor

Is there any fault in exhaust

system?

Repair or replace

faulty parts.

Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

15WRX_STI_US_EN.book 180 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-181

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

AZ:DTC P013A O2 SENSOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SEN-

SOR 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-68, DTC P013A O2 SENSOR SLOW RESPONSE -

RICH TO LEAN (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 181 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-182

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BA:DTC P013B O2 SENSOR SLOW RESPONSE - LEAN TO RICH (BANK 1 SEN-

SOR 2)

NOTE:

For the diagnostic procedure, refer to DTC P013A. <Ref. to EN(w/o STI)(diag)-181, DTC P013A O2 SEN-

SOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SENSOR 2), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

BB:DTC P013E O2 SENSOR DELAYED RESPONSE - RICH TO LEAN (BANK 1

SENSOR 2)

NOTE:

For the diagnostic procedure, refer to DTC P013A. <Ref. to EN(w/o STI)(diag)-181, DTC P013A O2 SEN-

SOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SENSOR 2), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

BC:DTC P013F O2 SENSOR DELAYED RESPONSE - LEAN TO RICH (BANK 1

SENSOR 2)

NOTE:

For the diagnostic procedure, refer to DTC P013A. <Ref. to EN(w/o STI)(diag)-181, DTC P013A O2 SEN-

SOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SENSOR 2), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 2. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

2 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

Measure the resistance between rear oxygen

sensor connector and engine ground.

Connector & terminal

(E25) No. 4 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 3. Repair the short

circuit to ground in

harness between

ECM connector

and rear oxygen

sensor connector.

3 CHECK REAR OXYGEN SENSOR.

Measure the resistance between rear oxygen

sensor terminals.

Terminals

No. 3 — No. 4

Is the resistance less than 1 Ω? Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

15WRX_STI_US_EN.book 182 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-183

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BD:DTC P0141 O2 SENSOR HEATER CIRCUIT (BANK1 SENSOR2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-76, DTC P0141 O2 SENSOR HEATER CIRCUIT

(BANK1 SENSOR2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 183 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-184

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY TO REAR OXY-

GEN SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from rear oxygen

sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between rear oxygen

sensor connector and engine ground.

Connector & terminal

(E25) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the power

supply line.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

A/F, oxygen sen-

sor relay and rear

oxygen sensor

connector

• Poor contact of

A/F, oxygen sen-

sor relay connector

• Poor contact of

coupling connector

• Malfunction of A/

F, oxygen sensor

relay

2 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and rear oxygen sensor connector.

Connector & terminal

(E25) No. 2 — (E159) No. 3:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

3 CHECK GROUND CIRCUIT FOR ECM.

Measure the resistance of harness between

ECM connector and engine ground.

Connector & terminal

(B134) No. 35 — Engine ground:

(B134) No. 47 — Engine ground:

(E159) No. 10 — Engine ground:

(E159) No. 17 — Engine ground:

(E159) No. 18 — Engine ground:

(E159) No. 25 — Engine ground:

(E159) No. 26 — Engine ground:

Is the resistance less than 5 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

coupling connector

4 CHECK REAR OXYGEN SENSOR.

Measure the resistance between rear oxygen

sensor connector terminals.

Terminals

No. 1 — No. 2:

Is the resistance 5.4 — 7.3 Ω? Repair the poor

contact of ECM

connector.

Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

15WRX_STI_US_EN.book 184 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-185

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BE:DTC P014C O2 SENSOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SEN-

SOR 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-77, DTC P014C O2 SENSOR SLOW RESPONSE -

RICH TO LEAN (BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

BF:DTC P014D O2 SENSOR SLOW RESPONSE - LEAN TO RICH (BANK 1 SEN-

SOR 1)

NOTE:

For the diagnostic procedure, refer to DTC P014C. <Ref. to EN(w/o STI)(diag)-185, DTC P014C O2 SEN-

SOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SENSOR 1), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

BG:DTC P015A O2 SENSOR DELAYED RESPONSE - RICH TO LEAN (BANK 1

SENSOR 1)

NOTE:

For the diagnostic procedure, refer to DTC P014C. <Ref. to EN(w/o STI)(diag)-185, DTC P014C O2 SEN-

SOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SENSOR 1), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

BH:DTC P015B O2 SENSOR DELAYED RESPONSE - LEAN TO RICH (BANK 1

SENSOR 1)

NOTE:

For the diagnostic procedure, refer to DTC P014C. <Ref. to EN(w/o STI)(diag)-185, DTC P014C O2 SEN-

SOR SLOW RESPONSE - RICH TO LEAN (BANK 1 SENSOR 1), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

BI: DTC P0171 SYSTEM TOO LEAN (BANK 1)

NOTE:

For the diagnostic procedure, refer to DTC P0172. <Ref. to EN(w/o STI)(diag)-186, DTC P0172 SYSTEM

TOO RICH (BANK 1), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

Step Check Yes No

1 CHECK EXHAUST SYSTEM.

NOTE:

Check the following items.

• Loose installation of front portion of exhaust

pipe onto cylinder heads

• Loose connection between front exhaust pipe

and front catalytic converter

• Damage of exhaust pipe resulting in a hole

Is there any fault in exhaust

system?

Repair the exhaust

system.

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

15WRX_STI_US_EN.book 185 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-186

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BJ:DTC P0172 SYSTEM TOO RICH (BANK 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-86, DTC P0172 SYSTEM TOO RICH (BANK 1), Diag-

nostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 186 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-187

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

#1 (E158) No. 11 — (E158) No. 12:

#2 (E158) No. 23 — (E158) No. 24:

#3 (E158) No. 35 — (E158) No. 36:

#4 (E158) No. 47 — (E158) No. 48:

Is resistance 1.89 — 2.31 Ω at

20°C (68°F)?

Go to step 3. Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Disconnect the connector from fuel injector.

2) Measure the resistance of harness between

ECM connector and defective fuel injector con-

nector.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Repair or replace

the following items.

• Poor contact of

fuel injector con-

nector

• Defective fuel

injector <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

3 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Disconnect the connector from fuel injector.

2) Measure the resistance between ECM con-

nector and engine ground on defective fuel

injectors.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the faulty

fuel injector. <Ref.

to FU(w/o STI)-51,

Fuel Injector.>

Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

5 CHECK EXHAUST SYSTEM. Are there holes or loose bolts

on exhaust system?

Repair the exhaust

system.

Go to step 6.

6 CHECK AIR INTAKE SYSTEM. Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

Go to step 7.

15WRX_STI_US_EN.book 187 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-188

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

7 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 328 —

358 kPa (3.3 — 3.7 kgf/cm

, 48

— 52 psi)?

Go to step 8. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

8 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

1) Start the engine and warm up completely.

2) Read the value of «Coolant Temp.» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Coolant Temp.»

75°C (167°F) or more?

Go to step 9. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

9 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Read the value of «Mass Air Flow» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Mass Air

Flow» 2.0 — 5.0 g/s (0.26 —

0.66 lb/m)?

Go to step 10. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 188 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-189

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

10 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Open the front hood.

6) Measure the ambient temperature.

7) Read the value of «IAT Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Subtract ambient temperature

value from the value of «IAT

Sensor #11». Is the obtained

value –10 — 50°C (–18 —

90°F)?

Go to step 11. Check the mass air

flow and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-118, Mass

Air Flow and Intake

Air Temperature

Sensor.>

11 CHECK FUEL INJECTOR.

Check fuel injector. <Ref. to FU(w/o STI)-70,

INSPECTION, Fuel Injector.>

Are fuel injectors OK? Repair the poor

contact of ECM

connector.

Replace the faulty

fuel injector. <Ref.

to FU(w/o STI)-51,

Fuel Injector.>

Step Check Yes No

15WRX_STI_US_EN.book 189 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-190

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BK:DTC P0191 FUEL RAIL PRESSURE SENSOR "A" CIRCUIT RANGE/PER-

FORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-87, DTC P0191 FUEL RAIL PRESSURE SENSOR "A"

CIRCUIT RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

213

E162

E158B:

E159C:

E162

C27

C19

EN-10324

ECM

FUEL

PRESSURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 190 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-191

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Fuel Rail Pressure A»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Fuel Rail

Pressure A» 2,500 kPa (25.49

kgf/cm

, 362.6 psi) or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK FUEL PRESSURE SENSOR POWER

SUPPLY.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the fuel

pressure sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between fuel pressure

sensor connector and engine ground.

Connector & terminal

(E162) No. 3 (+) — Engine ground (–):

Is the voltage 4.5 V or more? Go to step 3. Go to step 6.

3 CHECK FUEL PRESSURE SENSOR SIG-

NAL.

1) Connect all connectors.

2) Start the engine.

3) Read the value of «Fuel Rail Pressure A»

when idling using the Subaru Select Monitor or

a general scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

4) Measure the voltage between ECM connec-

tors.

Connector & terminal

(E158) No. 6 (+) — (E159) No. 27 (–):

When the value of «Fuel Rail

Pressure A» during idling is

approx. 4,000 kPa (40.79

kgf/cm

, 580.2 psi), is the

voltage 0.75 — 1.5 V?

Repair the poor

contact of ECM

connector.

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND

FUEL PRESSURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

fuel pressure sensor.

3) Measure the resistance of harness between

ECM connector and fuel pressure sensor con-

nector.

Connector & terminal

(E159) No. 27 — (E162) No. 1:

(E158) No. 6 — (E162) No. 2:

Is the resistance less than 1 Ω? Go to step 5. Repair the open

circuit in harness

between ECM con-

nector and fuel

pressure sensor

connector.

15WRX_STI_US_EN.book 191 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-192

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

5 CHECK HARNESS BETWEEN ECM AND

FUEL PRESSURE SENSOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 6 — Engine ground:

(E159) No. 27 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the fuel

pressure sensor.

<Ref. to FU(w/o

STI)-71, Fuel Pres-

sure Sensor.>

Repair the ground

short circuit of har-

ness between

ECM connector

and fuel pressure

sensor connector.

6 CHECK HARNESS BETWEEN ECM AND

FUEL PRESSURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and fuel pressure sensor con-

nector.

Connector & terminal

(E159) No. 19 — (E162) No. 3:

Is the resistance less than 1 Ω? Go to step 7. Repair the open

circuit in harness

between ECM con-

nector and fuel

pressure sensor

connector.

7 CHECK HARNESS BETWEEN ECM AND

FUEL PRESSURE SENSOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E159) No. 19 — Engine ground:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of ECM

connector.

Repair the ground

short circuit of har-

ness between

ECM connector

and fuel pressure

sensor connector.

Step Check Yes No

15WRX_STI_US_EN.book 192 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-193

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BL:DTC P0192 FUEL RAIL PRESSURE SENSOR CIRCUIT LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-88, DTC P0192 FUEL RAIL PRESSURE SENSOR CIR-

CUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

213

E162

E158B:

E159C:

E162

C27

C19

EN-10324

ECM

FUEL

PRESSURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 193 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-194

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Fuel Rail Pressure A»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Fuel Rail

Pressure A» approx. 0 kPa (0

kgf/cm

, 0 psi)?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND

FUEL PRESSURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

fuel pressure sensor.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 6 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the fuel

pressure sensor.

<Ref. to FU(w/o

STI)-71, Fuel Pres-

sure Sensor.>

Repair the ground

short circuit of har-

ness between

ECM connector

and fuel pressure

sensor connector.

15WRX_STI_US_EN.book 194 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-195

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BM:DTC P0193 FUEL RAIL PRESSURE SENSOR CIRCUIT HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-89, DTC P0193 FUEL RAIL PRESSURE SENSOR CIR-

CUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

213

E162

E158B:

E159C:

E162

C27

C19

EN-10324

ECM

FUEL

PRESSURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 195 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-196

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Fuel Rail Pressure A»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Fuel Rail

Pressure A» 30,000 kPa

(305.9 kgf/cm

, 4,351 psi) or

more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and fuel pres-

sure sensor connector.

Is there poor contact of the

ECM or fuel pressure sensor

connector?

Repair the poor

contact of the ECM

or fuel pressure

sensor connector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

FUEL PRESSURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

fuel pressure sensor.

3) Measure the resistance of harness between

ECM connector and fuel pressure sensor con-

nector.

Connector & terminal

(E159) No. 27 — (E162) No. 1:

(E158) No. 6 — (E162) No. 2:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit in harness

between ECM con-

nector and fuel

pressure sensor

connector.

4 CHECK HARNESS BETWEEN ECM AND

FUEL PRESSURE SENSOR CONNECTOR.

1) Connect all connectors.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E158) No. 6 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and fuel

pressure sensor

connector.

Replace the fuel

pressure sensor.

<Ref. to FU(w/o

STI)-71, Fuel Pres-

sure Sensor.>

15WRX_STI_US_EN.book 196 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-197

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BN:DTC P0196 ENGINE OIL TEMPERATURE SENSOR CIRCUIT RANGE/PER-

FORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-90, DTC P0196 ENGINE OIL TEMPERATURE SEN-

SOR CIRCUIT RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Hard to start

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

E158B:

E159C:

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E75

C27

EN-10325

ECM

ENGINE OIL

TEMPERATURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 197 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-198

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK ENGINE OIL TEMPERATURE SEN-

SOR.

1) Disconnect the connectors from the engine

oil temperature sensor.

2) Measure the resistance between engine oil

temperature sensor terminals when the engine

is cold and after warmed up.

Terminals

No. 1 — No. 2:

Is the resistance of engine oil

temperature sensor different

between when engine is cold

and after warmed up?

Repair the poor

contact of ECM

connector.

Replace the

engine oil tempera-

ture sensor. <Ref.

to FU(w/o STI)-96,

Engine Oil Temper-

ature Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 198 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-199

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BO:DTC P0197 ENGINE OIL TEMPERATURE SENSOR LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-92, DTC P0197 ENGINE OIL TEMPERATURE SEN-

SOR LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Hard to start

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

E159C:

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E75

C27

EN-10325

ECM

ENGINE OIL

TEMPERATURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 199 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-200

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Oil Temperature» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oil Tempera-

ture» 150°C (302°F) or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND EN-

GINE OIL TEMPERATURE SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the ECM

and engine oil temperature sensor.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the

engine oil tempera-

ture sensor. <Ref.

to FU(w/o STI)-96,

Engine Oil Temper-

ature Sensor.>

Repair the short

circuit to ground in

the harness

between the ECM

connector and

engine oil tempera-

ture sensor con-

nector.

15WRX_STI_US_EN.book 200 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-201

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BP:DTC P0198 ENGINE OIL TEMPERATURE SENSOR HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-93, DTC P0198 ENGINE OIL TEMPERATURE SEN-

SOR HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Hard to start

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

E159C:

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E75

C27

EN-10325

ECM

ENGINE OIL

TEMPERATURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 201 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-202

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Oil Temperature» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oil Tempera-

ture» –40°C (–40°F) or less?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK FOR POOR CONTACT.

Check for poor contact between the ECM and

engine oil temperature sensor connectors.

Is there poor contact of the

ECM or engine oil temperature

sensor connectors?

Repair the poor

contact of ECM or

engine oil tempera-

ture sensor con-

nector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND EN-

GINE OIL TEMPERATURE SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from the ECM

and engine oil temperature sensor.

3) Measure the resistance of the harness

between the ECM connector and engine oil

temperature sensor connector.

Connector & terminal

(E159) No. 27 — (E75) No. 1:

(E158) No. 2 — (E75) No. 2:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit in the har-

ness between

ECM connector

and engine oil tem-

perature sensor

connector.

4 CHECK HARNESS BETWEEN ECM AND EN-

GINE OIL TEMPERATURE SENSOR CON-

NECTOR.

1) Connect all connectors.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E158) No. 2 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

harness between

ECM connector

and engine oil tem-

perature sensor

connector.

Replace the

engine oil tempera-

ture sensor. <Ref.

to FU(w/o STI)-96,

Engine Oil Temper-

ature Sensor.>

15WRX_STI_US_EN.book 202 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-203

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BQ:DTC P0222 THROTTLE/PEDAL POSITION SENSOR/SWITCH “B” CIRCUIT

LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-94, DTC P0222 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “B” CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

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EN(w/o STI)(diag)-204

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

electronic throttle control.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 18 — Engine ground:

(E158) No. 29 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 2. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 204 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-205

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK SHORT CIRCUIT INSIDE THE ECM.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 4 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the elec-

tronic throttle con-

trol. <Ref. to FU(w/

o STI)-15, Throttle

Body.>

Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

Replace the ECM if

defective. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

Step Check Yes No

15WRX_STI_US_EN.book 205 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-206

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BR:DTC P0223 THROTTLE/PEDAL POSITION SENSOR/SWITCH “B” CIRCUIT

HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-95, DTC P0223 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “B” CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 206 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-207

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

electronic throttle control.

3) Measure the resistance of harness between

ECM connector and electronic throttle control

connector.

Connector & terminal

(E158) No. 29 — (E57) No. 4:

(E158) No. 30 — (E57) No. 3:

Is the resistance less than 1 Ω? Go to step 2. Repair the open

circuit of harness

between ECM con-

nector and elec-

tronic throttle

control connector.

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 207 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-208

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 3 — Engine ground:

Is the resistance less than 5 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

ECM connector

• Poor contact of

coupling connector

3 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 4 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 18 — (E158) No. 29:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of elec-

tronic throttle con-

trol connector.

Replace the elec-

tronic throttle con-

trol if defective.

<Ref. to FU(w/o

STI)-15, Throttle

Body.>

Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Step Check Yes No

15WRX_STI_US_EN.book 208 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-209

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BS:DTC P0230 FUEL PUMP PRIMARY CIRCUIT

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-96, DTC P0230 FUEL PUMP PRIMARY CIRCUIT, Di-

agnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B97

1234 56789

10 11 12 13 14 15 16 17 18 19 20

EN-10801

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

R122

63451

B134

R58

B97

B220

R58

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

R122

ECM

FUEL PUMP CU

BATTERY

FUEL PUMP RELAY

M/B No. 11

FUEL PUMP

(BROWN)

15WRX_STI_US_EN.book 209 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-210

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY CIRCUIT TO FUEL

PUMP CONTROL UNIT.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from fuel pump

control unit.

3) Turn the ignition switch to ON.

4) Measure the voltage between fuel pump

control unit connector and engine ground.

Connector & terminal

(R122) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the power

supply circuit.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in harness

between fuel pump

relay connector

and fuel pump con-

trol unit connector

• Poor contact of

fuel pump control

unit connector

• Poor contact of

fuel pump relay

connector

• Poor contact of

coupling connector

2 CHECK GROUND CIRCUIT OF FUEL PUMP

CONTROL UNIT.

1) Turn the ignition switch to OFF.

2) Measure the resistance of harness between

fuel pump control unit connector and engine

ground.

Connector & terminal

(R122) No. 4 — Engine ground:

Is the resistance less than 5 Ω? Go to step 3. Repair the open

circuit between fuel

pump control unit

connector and

engine ground.

3 CHECK HARNESS BETWEEN FUEL PUMP

CONTROL UNIT AND FUEL PUMP CONNEC-

TOR.

1) Disconnect the connector from fuel pump.

2) Measure the resistance of harness between

fuel pump control unit and fuel pump connector.

Connector & terminal

(R122) No. 5 — (R58) No. 4:

(R122) No. 6 — (R58) No. 3:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit in harness

between fuel pump

control unit con-

nector and fuel

pump connector.

4 CHECK HARNESS BETWEEN FUEL PUMP

CONTROL UNIT AND FUEL PUMP CONNEC-

TOR.

Measure the resistance between fuel pump

control unit connector and engine ground.

Connector & terminal

(R122) No. 5 — Engine ground:

(R122) No. 6 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

fuel pump control

unit connector and

fuel pump connec-

tor.

5 CHECK HARNESS BETWEEN ECM AND

FUEL PUMP CONTROL UNIT CONNECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance of harness between

ECM connector and fuel pump control unit con-

nector.

Connector & terminal

(B134) No. 40 — (R122) No. 2:

(B134) No. 44 — (R122) No. 3:

Is the resistance less than 1 Ω? Go to step 6. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and fuel pump con-

trol unit connector

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 210 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-211

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

6 CHECK HARNESS BETWEEN ECM AND

FUEL PUMP CONTROL UNIT CONNECTOR.

Measure the resistance between fuel pump

control unit connector and engine ground.

Connector & terminal

(R122) No. 2 — Engine ground:

(R122) No. 3 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 7. Repair the short

circuit to ground in

harness between

ECM connector

and fuel pump con-

trol unit connector.

7 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and fuel pump

control unit connector.

Is there poor contact of ECM or

fuel pump control unit connec-

tor?

Repair the poor

contact of ECM or

fuel pump control

unit connector.

Go to step 8.

8 CHECK EXPERIENCE OF RUNNING OUT OF

FUEL.

Has the vehicle experienced

running out of fuel?

Finish the diagno-

sis.

NOTE:

DTC may be re-

corded as a result

of fuel pump idling

while running out

of fuel.

Replace the fuel

pump control unit.

<Ref. to FU(w/o

STI)-145, Fuel

Pump Control

Unit.>

Step Check Yes No

15WRX_STI_US_EN.book 211 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-212

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BT:DTC P023F FUEL PUMP SECONDARY CIRCUIT/OPEN

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-97, DTC P023F FUEL PUMP SECONDARY CIRCUIT/

OPEN, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HIGH-PRESSURE FUEL PUMP.

Check the high-pressure fuel pump. <Ref. to

FU(w/o STI)-82, INSPECTION, High Pressure

Fuel Pump.>

Is the high-pressure fuel pump

normal?

Go to step 2. Replace the high-

pressure fuel

pump. <Ref. to

FU(w/o STI)-74,

High Pressure

Fuel Pump.>

E160

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

E160

EN-10802

ECM

HIGH-PRESSURE

FUEL PUMP

(BLACK)

15WRX_STI_US_EN.book 212 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-213

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK HARNESS BETWEEN ECM AND

HIGH-PRESSURE FUEL PUMP CONNEC-

TOR.

1) Disconnect the connector from ECM and

high-pressure fuel pump.

2) Measure the resistance of harness between

ECM connector and high-pressure fuel pump

connector.

Connector & terminal

(E158) No. 10 — (E160) No. 1:

(E158) No. 22 — (E160) No. 2:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit in harness

between ECM con-

nector and high-

pressure fuel

pump connector.

3 CHECK HARNESS BETWEEN ECM AND

HIGH-PRESSURE FUEL PUMP CONNEC-

TOR.

Measure the resistance between high-pressure

fuel pump connector and engine ground.

Connector & terminal

(E160) No. 1 — Engine ground:

(E160) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of ECM

connector.

Repair the short

circuit to ground in

harness between

ECM connector

and high-pressure

fuel pump connec-

tor.

Step Check Yes No

15WRX_STI_US_EN.book 213 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-214

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BU:DTC P0244 TURBO/SUPER CHARGER WASTEGATE SOLENOID “A”

RANGE/PERFORMANCE

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-98, DTC P0244 TURBO/SUPER CHARGER WASTE-

GATE SOLENOID “A” RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK WASTEGATE ACTUATOR PIPING

AND WASTEGATE CONTROL SOLENOID

VALVE PIPING.

Are there any damage or dis-

connection of hose in waste-

gate actuator piping or

wastegate control solenoid

valve piping?

Connect the

wastegate actuator

pipe or wastegate

control solenoid

valve pipe properly.

If defective,

replace the hose.

Replace the waste-

gate control sole-

noid valve. <Ref. to

FU(w/o STI)-123,

Wastegate Control

Solenoid Valve.>

15WRX_STI_US_EN.book 214 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-215

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BV:DTC P0245 TURBO/SUPER CHARGER WASTEGATE SOLENOID “A” LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-100, DTC P0245 TURBO/SUPER CHARGER WASTE-

GATE SOLENOID “A” LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK OUTPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 11 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

E64

B22

EN-10803

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

E159

E64

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

ECM

SBF-7

232221 262524201918

587

10 11

B550

(GRAY)

WASTEGATE CONTROL

SOLENOID VALVE

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 215 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-216

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

3 CHECK POWER SUPPLY TO WASTEGATE

CONTROL SOLENOID VALVE.

Measure the voltage between wastegate con-

trol solenoid valve connector and engine

ground.

Connector & terminal

(E64) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND

WASTEGATE CONTROL SOLENOID VALVE

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

wastegate control solenoid valve.

3) Measure the resistance between wastegate

control solenoid valve connector and engine

ground.

Connector & terminal

(E64) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair ground

short circuit of har-

ness between

ECM connector

and wastegate

control solenoid

valve connector.

5 CHECK HARNESS BETWEEN ECM AND

WASTEGATE CONTROL SOLENOID VALVE

CONNECTOR.

Measure the resistance of harness between

ECM connector and wastegate control solenoid

valve connector.

Connector & terminal

(E159) No. 11 — (E64) No. 2:

Is the resistance less than 1 Ω? Go to step 6. Repair open circuit

in harness

between ECM con-

nector and waste-

gate control

solenoid valve con-

nector.

6 CHECK WASTEGATE CONTROL SOLE-

NOID VALVE.

1) Remove the wastegate control solenoid

valve.

2) Measure the resistance between wastegate

control solenoid valve terminals.

Terminals

No. 1 — No. 2:

Is the resistance 10 — 100 Ω? Repair poor con-

tact of wastegate

control solenoid

valve connector.

Replace the waste-

gate control sole-

noid valve. <Ref. to

FU(w/o STI)-123,

Wastegate Control

Solenoid Valve.>

Step Check Yes No

15WRX_STI_US_EN.book 216 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-217

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BW:DTC P0246 TURBO/SUPER CHARGER WASTEGATE SOLENOID “A” HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-101, DTC P0246 TURBO/SUPER CHARGER WASTE-

GATE SOLENOID “A” HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

WASTEGATE CONTROL SOLENOID VALVE

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

wastegate control solenoid valve.

3) Turn the ignition switch to ON.

4) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 11 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair short cir-

cuit to power in

harness between

ECM connector

and wastegate

control solenoid

valve connector.

Go to step 2.

E64

B22

EN-10803

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

E159

E64

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

ECM

SBF-7

232221 262524201918

587

10 11

B550

(GRAY)

WASTEGATE CONTROL

SOLENOID VALVE

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 217 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-218

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK WASTEGATE CONTROL SOLE-

NOID VALVE.

1) Turn the ignition switch to OFF.

2) Measure the resistance between wastegate

control solenoid valve terminals.

Terminals

No. 1 — No. 2:

Is the resistance less than 1 Ω? Replace the waste-

gate control sole-

noid valve. <Ref. to

FU(w/o STI)-123,

Wastegate Control

Solenoid Valve.>

Repair the poor

contact of ECM

connector.

Step Check Yes No

15WRX_STI_US_EN.book 218 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-219

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BX:DTC P0300 RANDOM/MULTIPLE CYLINDER MISFIRE DETECTED

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• Immediately at fault recognition (A misfire which could damage catalyst occurs.)

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-101, DTC P0300 RANDOM/MULTIPLE CYLINDER

MISFIRE DETECTED, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

• Rough driving

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 219 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-220

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 220 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-221

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from all fuel injec-

tors.

3) Measure the resistance between all fuel

injector connectors and engine ground.

Connector & terminal

#1 (E5) No. 1 — Engine ground:

#1 (E5) No. 2 — Engine ground:

#2 (E16) No. 1 — Engine ground:

#2 (E16) No. 2 — Engine ground:

#3 (E6) No. 1 — Engine ground:

#3 (E6) No. 2 — Engine ground:

#4 (E17) No. 1 — Engine ground:

#4 (E17) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 2. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

2 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance of harness between

ECM connector and fuel injector connector on

all cylinders.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

3 CHECK FUEL INJECTOR.

Check all fuel injectors. <Ref. to FU(w/o STI)-

70, INSPECTION, Fuel Injector.>

Are fuel injectors OK? Go to step 4. Replace the faulty

fuel injector. <Ref.

to FU(w/o STI)-51,

Fuel Injector.>

4 CHECK INSTALLATION CONDITION OF

CAMSHAFT POSITION SENSOR/CRANK-

SHAFT POSITION SENSOR.

Is the camshaft position sensor

or crankshaft position sensor

loosely installed?

Tighten the cam-

shaft position sen-

sor or crankshaft

position sensor.

<Ref. to FU(w/o

STI)-104, INSTAL-

LATION, Cam-

shaft Position

Sensor.> <Ref. to

FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

Go to step 5.

5 CHECK CRANKSHAFT POSITION SENSOR

PLATE.

Is the crankshaft position sen-

sor plate rusted or does it have

broken teeth?

Replace the crank-

shaft position sen-

sor plate. <Ref. to

ME(w/o STI)-260,

Cylinder Block.>

Go to step 6.

6 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Turn the crankshaft using ST, and align the

alignment mark on crank sprocket with align-

ment mark on cylinder block.

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain dislocated

from its proper position?

Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

Go to step 7.

15WRX_STI_US_EN.book 221 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-222

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

7 CHECK FUEL LEVEL. Is the fuel meter indication

higher than the “Lower” level?

Go to step 8. Refill the fuel so

that the fuel meter

indication is higher

than the “Lower”

level, and proceed

to the next step. Go

to step 8.

8 CHECK STATUS OF MALFUNCTION INDI-

CATOR LIGHT.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, Clear Memory Mode.>

2) Start the engine, and drive the vehicle 10

minutes or more.

Does the malfunction indicator

light illuminate or blink?

Go to step 10. Go to step 9.

9 CHECK CAUSE OF MISFIRE. Was the cause of misfire identi-

fied when the engine is run-

ning?

Finish diagnostics

operation, if the

engine has no

abnormality.

Repair the poor

contact of connec-

tor.

NOTE:

In this case, repair

the following item:

• Poor contact of

ignition coil con-

nector

• Poor contact of

fuel injector con-

nector on faulty

cylinders

• Poor contact of

ECM connector

• Poor contact of

coupling connector

10 CHECK AIR INTAKE SYSTEM. Is there any fault in air intake

system?

Repair the air

intake system.

NOTE:

Check the follow-

ing items.

• Are there air

leaks or air suction

caused by loose or

dislocated nuts

and bolts?

• Are there cracks

or any disconnec-

tion of hoses?

Go to step 11.

11 CHECK ALL CYLINDERS. Is there a fault in any cylinder? Repair or replace

the faulty part of

the faulty cylinder.

NOTE:

Check the follow-

ing items.

• Spark plug

• Ignition coil

• Fuel injector

• Compression ra-

tio

• Skipping timing

chain teeth

Go to DTC P0171.

<Ref. to EN(w/o

STI)(diag)-185,

DTC P0171 SYS-

TEM TOO LEAN

(BANK 1), Diag-

nostic Procedure

with Diagnostic

Trouble Code

(DTC).>

Step Check Yes No

15WRX_STI_US_EN.book 222 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-223

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

BY:DTC P0301 CYLINDER 1 MISFIRE DETECTED

NOTE:

For the diagnostic procedure, refer to DTC P0304. <Ref. to EN(w/o STI)(diag)-224, DTC P0304 CYLINDER

4 MISFIRE DETECTED, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

BZ:DTC P0302 CYLINDER 2 MISFIRE DETECTED

NOTE:

For the diagnostic procedure, refer to DTC P0304. <Ref. to EN(w/o STI)(diag)-224, DTC P0304 CYLINDER

4 MISFIRE DETECTED, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

CA:DTC P0303 CYLINDER 3 MISFIRE DETECTED

NOTE:

For the diagnostic procedure, refer to DTC P0304. <Ref. to EN(w/o STI)(diag)-224, DTC P0304 CYLINDER

4 MISFIRE DETECTED, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

15WRX_STI_US_EN.book 223 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-224

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CB:DTC P0304 CYLINDER 4 MISFIRE DETECTED

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• Immediately at fault recognition (A misfire which could damage catalyst occurs.)

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-106, DTC P0304 CYLINDER 4 MISFIRE DETECTED,

Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

• Rough driving

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 224 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-225

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 225 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-226

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from fuel injector

on faulty cylinders.

3) Measure the resistance between fuel injec-

tor connector and engine ground on faulty cylin-

ders.

Connector & terminal

#1 (E5) No. 1 — Engine ground:

#1 (E5) No. 2 — Engine ground:

#2 (E16) No. 1 — Engine ground:

#2 (E16) No. 2 — Engine ground:

#3 (E6) No. 1 — Engine ground:

#3 (E6) No. 2 — Engine ground:

#4 (E17) No. 1 — Engine ground:

#4 (E17) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 2. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

2 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance of harness between

ECM connector and fuel injector connector on

faulty cylinders.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

3 CHECK FUEL INJECTOR.

Check the fuel injector on faulty cylinder. <Ref.

to FU(w/o STI)-70, INSPECTION, Fuel Injec-

tor.>

Are fuel injectors OK? Go to step 4. Replace the faulty

fuel injector. <Ref.

to FU(w/o STI)-51,

Fuel Injector.>

4 CHECK INSTALLATION CONDITION OF

CAMSHAFT POSITION SENSOR/CRANK-

SHAFT POSITION SENSOR.

Is the camshaft position sensor

or crankshaft position sensor

loosely installed?

Tighten the cam-

shaft position sen-

sor or crankshaft

position sensor.

<Ref. to FU(w/o

STI)-104, INSTAL-

LATION, Cam-

shaft Position

Sensor.> <Ref. to

FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

Go to step 5.

5 CHECK CRANKSHAFT POSITION SENSOR

PLATE.

Is the crankshaft position sen-

sor plate rusted or does it have

broken teeth?

Replace the crank-

shaft position sen-

sor plate. <Ref. to

ME(w/o STI)-260,

Cylinder Block.>

Go to step 6.

6 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Turn the crankshaft using ST, and align the

alignment mark on crank sprocket with align-

ment mark on cylinder block.

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain dislocated

from its proper position?

Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

Go to step 7.

15WRX_STI_US_EN.book 226 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-227

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

7 CHECK FUEL LEVEL. Is the fuel meter indication

higher than the “Lower” level?

Go to step 8. Refill the fuel so

that the fuel meter

indication is higher

than the “Lower”

level, and proceed

to the next step. Go

to step 8.

8 CHECK STATUS OF MALFUNCTION INDI-

CATOR LIGHT.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, Clear Memory Mode.>

2) Start the engine, and drive the vehicle 10

minutes or more.

Does the malfunction indicator

light illuminate or blink?

Go to step 10. Go to step 9.

9 CHECK CAUSE OF MISFIRE. Was the cause of misfire identi-

fied when the engine is run-

ning?

Finish diagnostics

operation, if the

engine has no

abnormality.

Repair the poor

contact of connec-

tor.

NOTE:

In this case, repair

the following item:

• Poor contact of

ignition coil con-

nector

• Poor contact of

fuel injector con-

nector on faulty

cylinders

• Poor contact of

ECM connector

• Poor contact of

coupling connector

10 CHECK AIR INTAKE SYSTEM. Is there any fault in air intake

system?

Repair the air

intake system.

NOTE:

Check the follow-

ing items.

• Are there air

leaks or air suction

caused by loose or

dislocated nuts

and bolts?

• Are there cracks

or any disconnec-

tion of hoses?

Go to step 11.

11 CHECK CYLINDER. Is there any fault in the cylin-

der?

Repair or replace

faulty parts.

NOTE:

Check the follow-

ing items.

• Spark plug

• Ignition coil

• Fuel injector

• Compression ra-

tio

• Skipping timing

chain teeth

Go to DTC P0171.

<Ref. to EN(w/o

STI)(diag)-185,

DTC P0171 SYS-

TEM TOO LEAN

(BANK 1), Diag-

nostic Procedure

with Diagnostic

Trouble Code

(DTC).>

Step Check Yes No

15WRX_STI_US_EN.book 227 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-228

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CC:DTC P0327 KNOCK SENSOR 1 CIRCUIT LOW (BANK 1 OR SINGLE SEN-

SOR)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-107, DTC P0327 KNOCK SENSOR 1 CIRCUIT LOW

(BANK 1 OR SINGLE SENSOR), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Poor driving performance

• Knocking occurs

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

KNOCK SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 14 — (E159) No. 27:

Is the resistance less than 500

kΩ?

Go to step 2. Go to step 3.

E14

EN-10804

E158B:

E159C:

C27

B14

E48

2B26

E14 E48

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

ECM

(GRAY)

(BLACK)

KNOCK SENSOR LH

KNOCK SENSOR RH

15WRX_STI_US_EN.book 228 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-229

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK KNOCK SENSOR.

1) Disconnect the connector from the knock

sensor.

2) Measure the resistance between knock

sensor connectors.

Terminals

No. 1 — No. 2:

Is the resistance less than 500

kΩ?

Replace the knock

sensor. <Ref. to

FU(w/o STI)-111,

Knock Sensor.>

Repair the short

circuit to ground in

harness between

ECM connector

and knock sensor

connector.

NOTE:

The harness be-

tween both con-

nectors are

shielded. Remove

the shield and re-

pair the short cir-

cuit of harness.

3 CHECK INPUT SIGNAL OF ECM.

1) Connect the ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E158) No. 14 (+) — Engine ground (–):

Is the voltage 2 V or more? Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

Repair the short

circuit to ground in

harness between

ECM connector

and knock sensor

connector.

NOTE:

The harness be-

tween both con-

nectors are

shielded. Remove

the shield and re-

pair the short cir-

cuit of harness.

Step Check Yes No

15WRX_STI_US_EN.book 229 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-230

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CD:DTC P0328 KNOCK SENSOR 1 CIRCUIT HIGH (BANK 1 OR SINGLE SEN-

SOR)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-108, DTC P0328 KNOCK SENSOR 1 CIRCUIT HIGH

(BANK 1 OR SINGLE SENSOR), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Poor driving performance

• Knocking occurs

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

KNOCK SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 14 — (E159) No. 27:

Is the resistance 600 kΩ or

more?

Go to step 2. Repair the poor

contact of ECM

connector.

E14

EN-10804

E158B:

E159C:

C27

B14

E48

2B26

E14 E48

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

ECM

(GRAY)

(BLACK)

KNOCK SENSOR LH

KNOCK SENSOR RH

15WRX_STI_US_EN.book 230 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-231

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK KNOCK SENSOR.

1) Disconnect the connector from the knock

sensor.

2) Measure the resistance between knock

sensor terminals.

Terminals

No. 1 — No. 2:

Is the resistance 600 kΩ or

more?

Replace the knock

sensor. <Ref. to

FU(w/o STI)-111,

Knock Sensor.>

Repair the open

circuit in harness

between ECM con-

nector and knock

sensor connector.

Step Check Yes No

15WRX_STI_US_EN.book 231 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-232

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CE:DTC P0332 KNOCK SENSOR 2 CIRCUIT LOW (BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-109, DTC P0332 KNOCK SENSOR 2 CIRCUIT LOW

(BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Driving performance problem

• Knocking occurs

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

KNOCK SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 26 — (E159) No. 27:

Is the resistance less than 500

kΩ?

Go to step 2. Go to step 3.

E14

EN-10804

E158B:

E159C:

C27

B14

E48

2B26

E14 E48

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

ECM

(GRAY)

(BLACK)

KNOCK SENSOR LH

KNOCK SENSOR RH

15WRX_STI_US_EN.book 232 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-233

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK KNOCK SENSOR.

1) Disconnect the connector from the knock

sensor.

2) Measure the resistance between knock

sensor connectors.

Terminals

No. 1 — No. 2:

Is the resistance less than 500

kΩ?

Replace the knock

sensor. <Ref. to

FU(w/o STI)-111,

Knock Sensor.>

Repair the short

circuit to ground in

harness between

ECM connector

and knock sensor

connector.

NOTE:

The harness be-

tween both con-

nectors are

shielded. Remove

the shield and re-

pair the short cir-

cuit of harness.

3 CHECK INPUT SIGNAL OF ECM.

1) Connect the ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E158) No. 26 (+) — Engine ground (–):

Is the voltage 2 V or more? Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

Repair the short

circuit to ground in

harness between

ECM connector

and knock sensor

connector.

NOTE:

The harness be-

tween both con-

nectors are

shielded. Remove

the shield and re-

pair the short cir-

cuit of harness.

Step Check Yes No

15WRX_STI_US_EN.book 233 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-234

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CF:DTC P0333 KNOCK SENSOR 2 CIRCUIT HIGH (BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-110, DTC P0333 KNOCK SENSOR 2 CIRCUIT HIGH

(BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Driving performance problem

• Knocking occurs

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

KNOCK SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 26 — (E159) No. 27:

Is the resistance 600 kΩ or

more?

Go to step 2. Repair the poor

contact of ECM

connector.

E14

EN-10804

E158B:

E159C:

C27

B14

E48

2B26

E14 E48

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

ECM

(GRAY)

(BLACK)

KNOCK SENSOR LH

KNOCK SENSOR RH

15WRX_STI_US_EN.book 234 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-235

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK KNOCK SENSOR.

1) Disconnect the connector from the knock

sensor.

2) Measure the resistance between knock

sensor terminals.

Terminals

No. 1 — No. 2:

Is the resistance 600 kΩ or

more?

Replace the knock

sensor. <Ref. to

FU(w/o STI)-111,

Knock Sensor.>

Repair the open

circuit in harness

between ECM con-

nector and knock

sensor connector.

Step Check Yes No

15WRX_STI_US_EN.book 235 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-236

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CG:DTC P0335 CRANKSHAFT POSITION SENSOR “A” CIRCUIT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-111, DTC P0335 CRANKSHAFT POSITION SENSOR

“A” CIRCUIT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

EN-10805

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

E158

E10

B22

5678

10 11 12

1413 15 16

E10

213

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

ECM

SBF-7

232221 262524201918

587

10 11

B550

(BLACK)

CRANKSHAFT

POSITION SENSOR

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 236 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-237

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY OF CRANKSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the crank-

shaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in harness

between main re-

lay connector and

crankshaft posi-

tion sensor con-

nector

• Poor contact of

coupling connector

2 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and crankshaft position sensor connec-

tor.

Connector & terminal

(E158) No. 19 — (E10) No. 2:

(E158) No. 31 — (E10) No. 3:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit in the har-

ness between the

ECM connector

and crankshaft

position sensor

connector.

3 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

Measure the resistance between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 2 — Engine ground:

(E10) No. 3 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair short cir-

cuit to ground in

harness between

ECM connector

and crankshaft

position sensor

connector.

4 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

Measure the voltage between crankshaft posi-

tion sensor connector and engine ground.

Connector & terminal

(E10) No. 2 (+) — Engine ground (–):

(E10) No. 3 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and crank-

shaft position

sensor connector.

Go to step 5.

5 CHECK CONDITION OF CRANKSHAFT PO-

SITION SENSOR.

Is the crankshaft position sen-

sor installation bolt tightened

securely?

Go to step 6. Tighten the crank-

shaft position sen-

sor installation bolt

securely. <Ref. to

FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

6 CHECK CRANKSHAFT POSITION SENSOR.

Check waveform of crankshaft position sensor.

<Ref. to EN(w/o STI)(diag)-20, Engine Control

Module (ECM) I/O Signal.>

Is there any abnormality in

waveform?

Replace the crank-

shaft position sen-

sor. <Ref. to FU(w/

o STI)-103, Cam-

shaft Position Sen-

sor.>

Repair the follow-

ing item.

• Poor contact of

ECM connector

• Poor contact of

crankshaft posi-

tion sensor con-

nector

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 237 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-238

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CH:DTC P0336 CRANKSHAFT POSITION SENSOR “A” CIRCUIT RANGE/PER-

FORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-113, DTC P0336 CRANKSHAFT POSITION SENSOR

“A” CIRCUIT RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK CONDITION OF CRANKSHAFT PO-

SITION SENSOR.

Turn the ignition switch to OFF.

Is the crankshaft position sen-

sor installation bolt tightened

securely?

Go to step 2. Tighten the crank-

shaft position sen-

sor installation bolt

securely. <Ref. to

FU(w/o STI)-98,

Crankshaft Posi-

tion Sensor.>

2 CHECK CRANKSHAFT POSITION SENSOR

PLATE.

Is there crack or damage in the

crankshaft position sensor

plate teeth?

Replace the crank-

shaft position sen-

sor plate. <Ref. to

ME(w/o STI)-260,

Cylinder Block.>

Go to step 3.

3 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Turn the crankshaft, and align alignment mark

on crank sprocket with alignment mark on cylin-

der block.

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain dislocated

from its proper position?

Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

Replace the crank-

shaft position sen-

sor. <Ref. to FU(w/

o STI)-98, Crank-

shaft Position Sen-

sor.>

15WRX_STI_US_EN.book 238 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-239

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CI: DTC P0340 CAMSHAFT POSITION SENSOR “A” CIRCUIT (BANK 1 OR SIN-

GLE SENSOR)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-115, DTC P0340 CAMSHAFT POSITION SENSOR “A”

CIRCUIT (BANK 1 OR SINGLE SENSOR), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

EN-10806

B550

215

B220

E36

E35

213

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E158

E35

E36

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BLACK)

INTAKE CAMSHAFT

POSITION SENSOR RH

INTAKE CAMSHAFT

POSITION SENSOR LH

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 239 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-240

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY OF CAMSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from camshaft

position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between camshaft

position sensor connector and engine ground.

Connector & terminal

(E36) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in harness

between main re-

lay connector and

camshaft position

sensor connector

• Poor contact of

coupling connector

2 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and camshaft position sensor connector.

Connector & terminal

(E158) No. 20 — (E36) No. 2:

(E158) No. 34 — (E36) No. 3:

Is the resistance less than 1 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and camshaft posi-

tion sensor con-

nector

• Poor contact of

coupling connector

3 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

Measure the resistance between camshaft

position sensor connector and engine ground.

Connector & terminal

(E36) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair short cir-

cuit to ground in

harness between

ECM connector

and camshaft posi-

tion sensor con-

nector.

4 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

Measure the voltage between camshaft posi-

tion sensor connector and engine ground.

Connector & terminal

(E36) No. 2 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and cam-

shaft position

sensor connector.

Go to step 5.

5 CHECK CONDITION OF CAMSHAFT POSI-

TION SENSOR.

Is the camshaft position sensor

installation bolt tightened

securely?

Go to step 6. Tighten the cam-

shaft position sen-

sor installation bolt

securely. <Ref. to

FU(w/o STI)-104,

INSTALLATION,

Camshaft Position

Sensor.>

6 CHECK CAMSHAFT POSITION SENSOR.

Check the waveform of the camshaft position

sensor. <Ref. to EN(w/o STI)(diag)-20, Engine

Control Module (ECM) I/O Signal.>

Is there any abnormality in

waveform?

Replace the cam-

shaft position sen-

sor. <Ref. to FU(w/

o STI)-103, Cam-

shaft Position Sen-

sor.>

Repair the follow-

ing item.

• Poor contact of

ECM connector

• Poor contact of

camshaft position

sensor connector

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 240 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-241

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CJ:DTC P0341 CAMSHAFT POSITION SENSOR "A" CIRCUIT RANGE/PERFOR-

MANCE (BANK 1 OR SINGLE SENSOR)

NOTE:

For the diagnostic procedure, refer to DTC P0340. <Ref. to EN(w/o STI)(diag)-239, DTC P0340 CAMSHAFT

POSITION SENSOR “A” CIRCUIT (BANK 1 OR SINGLE SENSOR), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

15WRX_STI_US_EN.book 241 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-242

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CK:DTC P0345 CAMSHAFT POSITION SENSOR “A” CIRCUIT (BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-118, DTC P0345 CAMSHAFT POSITION SENSOR “A”

CIRCUIT (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

EN-10806

B550

215

B220

E36

E35

213

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E158

E35

E36

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BLACK)

INTAKE CAMSHAFT

POSITION SENSOR RH

INTAKE CAMSHAFT

POSITION SENSOR LH

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 242 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-243

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY OF CAMSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from camshaft

position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between camshaft

position sensor connector and engine ground.

Connector & terminal

(E35) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in harness

between main re-

lay connector and

camshaft position

sensor connector

• Poor contact of

coupling connector

2 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and camshaft position sensor connector.

Connector & terminal

(E158) No. 21 — (E35) No. 2:

(E158) No. 34 — (E35) No. 3:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit in the har-

ness between the

ECM connector

and camshaft posi-

tion sensor con-

nector.

3 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

Measure the resistance between camshaft

position sensor connector and engine ground.

Connector & terminal

(E35) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair short cir-

cuit to ground in

harness between

ECM connector

and camshaft posi-

tion sensor con-

nector.

4 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

Measure the voltage between camshaft posi-

tion sensor connector and engine ground.

Connector & terminal

(E35) No. 2 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and cam-

shaft position

sensor connector.

Go to step 5.

5 CHECK CONDITION OF CAMSHAFT POSI-

TION SENSOR.

Is the camshaft position sensor

installation bolt tightened

securely?

Go to step 6. Tighten the cam-

shaft position sen-

sor installation bolt

securely. <Ref. to

FU(w/o STI)-104,

INSTALLATION,

Camshaft Position

Sensor.>

6 CHECK CAMSHAFT POSITION SENSOR.

Check the waveform of the camshaft position

sensor. <Ref. to EN(w/o STI)(diag)-20, Engine

Control Module (ECM) I/O Signal.>

Is there any abnormality in

waveform?

Replace the cam-

shaft position sen-

sor. <Ref. to FU(w/

o STI)-103, Cam-

shaft Position Sen-

sor.>

Repair the follow-

ing item.

• Poor contact of

ECM connector

• Poor contact of

camshaft position

sensor connector

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 243 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-244

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CL:DTC P0346 CAMSHAFT POSITION SENSOR "A" CIRCUIT RANGE/PERFOR-

MANCE (BANK 2)

NOTE:

For the diagnostic procedure, refer to DTC P0345. <Ref. to EN(w/o STI)(diag)-242, DTC P0345 CAMSHAFT

POSITION SENSOR “A” CIRCUIT (BANK 2), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

15WRX_STI_US_EN.book 244 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-245

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CM:DTC P0351 IGNITION COIL A PRIMARY/SECONDARY CIRCUIT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-119, DTC P0351 IGNITION COIL A PRIMARY/SEC-

ONDARY CIRCUIT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

ECM

E34

E32

E33

E31

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

B220

B550

216

E3B22

E31

E159

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10793

E32

E33

E34

232221 262524201918

587

10 11

B550

SBF-7

IGNITION COIL No. 4

IGNITION COIL No. 3

IGNITION COIL No. 2

IGNITION COIL No. 1

BATTERY

FUSE HOLDER

IG RELAY

(GRAY)

15WRX_STI_US_EN.book 245 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-246

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK IGNITION COIL POWER SUPPLY

CIRCUIT.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ignition coil.

3) Turn the ignition switch to ON.

4) Measure the voltage between ignition coil

connector and engine ground.

Connector & terminal

DTC P0351; (E31) No. 1 (+) — Engine

ground (–):

DTC P0352; (E32) No. 1 (+) — Engine

ground (–):

DTC P0353; (E33) No. 1 (+) — Engine

ground (–):

DTC P0354; (E34) No. 1 (+) — Engine

ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in harness

of power supply

circuit

• Blown out of fuse

• Poor contact of

IG relay connector

• Poor contact of

coupling connector

• Faulty IG relay

2 CHECK HARNESS OF IGNITION COIL

GROUND CIRCUIT.

1) Turn the ignition switch to OFF.

2) Measure the resistance of harness between

ignition coil connector and engine ground.

Connector & terminal

DTC P0351; (E31) No. 3 — Engine ground:

DTC P0352; (E32) No. 3 — Engine ground:

DTC P0353; (E33) No. 3 — Engine ground:

DTC P0354; (E34) No. 3 — Engine ground:

Is the resistance less than 5 Ω? Go to step 3. Repair the open

circuit in harness

between ignition

coil connector and

engine grounding

terminal.

3 CHECK HARNESS BETWEEN ECM AND IG-

NITION COIL CONNECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance between ignition

coil connector and engine ground.

Connector & terminal

DTC P0351; (E31) No. 2 — Engine ground:

DTC P0352; (E32) No. 2 — Engine ground:

DTC P0353; (E33) No. 2 — Engine ground:

DTC P0354; (E34) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair the ground

short circuit of har-

ness between

ECM connector

and ignition coil

connector.

4 CHECK HARNESS BETWEEN ECM AND IG-

NITION COIL CONNECTOR.

Measure the resistance of harness between

ECM connector and ignition coil connector.

Connector & terminal

DTC P0351; (E159) No. 8 — (E31) No. 2:

DTC P0352; (E159) No. 16 — (E32) No. 2:

DTC P0353; (E159) No. 24 — (E33) No. 2:

DTC P0354; (E159) No. 32 — (E34) No. 2:

Is the resistance less than 1 Ω? Go to step 5. Repair the open

circuit in harness

between ECM con-

nector and ignition

coil connector.

5 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Go to step 6.

6 CHECK SPARK PLUG CONDITION.

1) Remove the spark plug of the correspond-

ing cylinder. <Ref. to IG(w/o STI)-4, REMOVAL,

Spark Plug.>

2) Check the spark plug condition. <Ref. to

IG(w/o STI)-8, INSPECTION, Spark Plug.>

Is the spark plug condition nor-

mal?

Replace the igni-

tion coil. <Ref. to

IG(w/o STI)-11,

Ignition Coil.>

Replace the spark

plug. <Ref. to IG(w/

o STI)-4, Spark

Plug.>

15WRX_STI_US_EN.book 246 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-247

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CN:DTC P0352 IGNITION COIL B PRIMARY/SECONDARY CIRCUIT

NOTE:

For the diagnostic procedure, refer to DTC P0351. <Ref. to EN(w/o STI)(diag)-245, DTC P0351 IGNITION

COIL A PRIMARY/SECONDARY CIRCUIT, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

CO:DTC P0353 IGNITION COIL C PRIMARY/SECONDARY CIRCUIT

NOTE:

For the diagnostic procedure, refer to DTC P0351. <Ref. to EN(w/o STI)(diag)-245, DTC P0351 IGNITION

COIL A PRIMARY/SECONDARY CIRCUIT, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

CP:DTC P0354 IGNITION COIL D PRIMARY/SECONDARY CIRCUIT

NOTE:

For the diagnostic procedure, refer to DTC P0351. <Ref. to EN(w/o STI)(diag)-245, DTC P0351 IGNITION

COIL A PRIMARY/SECONDARY CIRCUIT, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

15WRX_STI_US_EN.book 247 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-248

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CQ:DTC P0365 CAMSHAFT POSITION SENSOR “B” CIRCUIT (BANK 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-120, DTC P0365 CAMSHAFT POSITION SENSOR “B”

CIRCUIT (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK POWER SUPPLY OF CAMSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from camshaft

position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between camshaft

position sensor connector and engine ground.

Connector & terminal

(E62) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

main relay and

camshaft position

sensor connector

• Poor contact of

coupling connector

B22

EN-10807

B550

215

B220

E65

E62

213

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E158

E65

E62

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

SBF-7

ECM

(BLACK)

EXHAUST CAMSHAFT

POSITION SENSOR RH

EXHAUST CAMSHAFT

POSITION SENSOR LH

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 248 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-249

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CR:DTC P0366 CAMSHAFT POSITION SENSOR B CIRCUIT RANGE/PERFOR-

MANCE (BANK 1)

NOTE:

For the diagnostic procedure, refer to DTC P0365. <Ref. to EN(w/o STI)(diag)-248, DTC P0365 CAMSHAFT

POSITION SENSOR “B” CIRCUIT (BANK 1), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

2 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and camshaft position sensor connector.

Connector & terminal

(E158) No. 32 — (E62) No. 2:

(E158) No. 34 — (E62) No. 3:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit in the har-

ness between the

ECM connector

and camshaft posi-

tion sensor con-

nector.

3 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

Measure the resistance between camshaft

position sensor connector and engine ground.

Connector & terminal

(E62) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair short cir-

cuit to ground in

harness between

ECM connector

and camshaft posi-

tion sensor con-

nector.

4 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

Measure the voltage between camshaft posi-

tion sensor connector and engine ground.

Connector & terminal

(E62) No. 2 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and cam-

shaft position

sensor connector.

Go to step 5.

5 CHECK CONDITION OF CAMSHAFT POSI-

TION SENSOR.

Is the camshaft position sensor

installation bolt tightened

securely?

Go to step 6. Tighten the cam-

shaft position sen-

sor installation bolt

securely. <Ref. to

FU(w/o STI)-104,

INSTALLATION,

Camshaft Position

Sensor.>

6 CHECK CAMSHAFT POSITION SENSOR.

Check the waveform of the camshaft position

sensor. <Ref. to EN(w/o STI)(diag)-20, Engine

Control Module (ECM) I/O Signal.>

Is there any abnormality in

waveform?

Replace the cam-

shaft position sen-

sor. <Ref. to FU(w/

o STI)-103, Cam-

shaft Position Sen-

sor.>

Repair the follow-

ing item.

• Poor contact of

ECM connector

• Poor contact of

camshaft position

sensor connector

• Poor contact of

coupling connector

Step Check Yes No

15WRX_STI_US_EN.book 249 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-250

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CS:DTC P0390 CAMSHAFT POSITION SENSOR “B” CIRCUIT (BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-122, DTC P0390 CAMSHAFT POSITION SENSOR “B”

CIRCUIT (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

EN-10807

B550

215

B220

E65

E62

213

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E158

E65

E62

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

SBF-7

ECM

(BLACK)

EXHAUST CAMSHAFT

POSITION SENSOR RH

EXHAUST CAMSHAFT

POSITION SENSOR LH

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 250 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-251

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY OF CAMSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from camshaft

position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between camshaft

position sensor connector and engine ground.

Connector & terminal

(E65) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in harness

between main re-

lay connector and

camshaft position

sensor connector

• Poor contact of

coupling connector

2 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and camshaft position sensor connector.

Connector & terminal

(E158) No. 33 — (E65) No. 2:

(E158) No. 34 — (E65) No. 3:

Is the resistance less than 1 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and camshaft posi-

tion sensor con-

nector

• Poor contact of

coupling connector

3 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

Measure the resistance between camshaft

position sensor connector and engine ground.

Connector & terminal

(E65) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair short cir-

cuit to ground in

harness between

ECM connector

and camshaft posi-

tion sensor con-

nector.

4 CHECK HARNESS BETWEEN ECM AND

CAMSHAFT POSITION SENSOR CONNEC-

TOR.

Measure the voltage between camshaft posi-

tion sensor connector and engine ground.

Connector & terminal

(E65) No. 2 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and cam-

shaft position

sensor connector.

Go to step 5.

5 CHECK CONDITION OF CAMSHAFT POSI-

TION SENSOR.

Is the camshaft position sensor

installation bolt tightened

securely?

Go to step 6. Tighten the cam-

shaft position sen-

sor installation bolt

securely. <Ref. to

FU(w/o STI)-104,

INSTALLATION,

Camshaft Position

Sensor.>

6 CHECK CAMSHAFT POSITION SENSOR.

Check the waveform of the camshaft position

sensor. <Ref. to EN(w/o STI)(diag)-20, Engine

Control Module (ECM) I/O Signal.>

Is there any abnormality in

waveform?

Replace the cam-

shaft position sen-

sor. <Ref. to FU(w/

o STI)-103, Cam-

shaft Position Sen-

sor.>

Repair the follow-

ing item.

• Poor contact of

ECM connector

• Poor contact of

camshaft position

sensor connector

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 251 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-252

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CT:DTC P0391 CAMSHAFT POSITION SENSOR B CIRCUIT RANGE/PERFOR-

MANCE (BANK 2)

NOTE:

For the diagnostic procedure, refer to DTC P0390. <Ref. to EN(w/o STI)(diag)-250, DTC P0390 CAMSHAFT

POSITION SENSOR “B” CIRCUIT (BANK 2), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

15WRX_STI_US_EN.book 252 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-253

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CU:DTC P0400 EXHAUST GAS RECIRCULATION FLOW

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-123, DTC P0400 EXHAUST GAS RECIRCULATION

FLOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Movement performance problem when engine is low speed.

• Improper idling

• Movement performance problem

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «Mani. Absolute Pres-

sure» using the Subaru Select Monitor or a gen-

eral scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Mani. Absolute

Pressure» 53.3 kPa (400

mmHg, 15.75 inHg) or more?

Make sure that the

EGR control valve,

manifold absolute

pressure sensor

and throttle body

are installed

securely.

Go to step 2.

2 CHECK EGR CONTROL VALVE.

Remove the EGR control valve.

Are there any holes, clogged

lines or foreign matters in the

EGR system?

Repair the EGR

system.

Replace EGR con-

trol valve. <Ref. to

EC(w/o STI)-35,

EGR Control

Valve.>

15WRX_STI_US_EN.book 253 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-254

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CV:DTC P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD (BANK 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-126, DTC P0420 CATALYST SYSTEM EFFICIENCY

BELOW THRESHOLD (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Idle mixture is out of specifications.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 254 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-255

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK EXHAUST SYSTEM.

Check for gas leaks or air suction caused by

loose or dislocated nuts and bolts, and open

hole at exhaust pipes.

NOTE:

Check the following positions.

• Between cylinder head and front exhaust

pipe

• Between front exhaust pipe and front catalytic

converter

• Between front catalytic converter and rear

catalytic converter

• Loose or improperly attached front oxygen

(A/F) sensor or rear oxygen sensor

Is there any fault in exhaust

system?

Repair or replace

the exhaust sys-

tem. <Ref. to

EX(w/o STI)-2,

General Descrip-

tion.>

Go to step 2.

2 CHECK WAVEFORM DATA ON THE SUBA-

RU SELECT MONITOR (WHILE DRIVING).

1) Drive at a constant speed between 80 —

112 km/h (50 — 70 MPH).

2) After 5 minutes have elapsed in the condi-

tion of step 1), use the Subaru Select Monitor

while still driving to read the waveform data.

• At normal condition

• At abnormal condition (numerous inversion)

Is a normal waveform dis-

played?

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

Go to step 3.

EN-06666

1.5

0.5

10 sec/div

REAR OXYGEN

SENSOR VOLTAGE

(V)

A/F SENSOR

OUTPUT LAMBDA 1

EN-06667

1.5

0.5

10 sec/div

REAR OXYGEN

SENSOR VOLTAGE

(V)

A/F SENSOR

OUTPUT LAMBDA 1

15WRX_STI_US_EN.book 255 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-256

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

3 CHECK WAVEFORM DATA ON THE SUBA-

RU SELECT MONITOR (WHILE IDLING).

1) Run the engine at idle.

2) In the condition of step 1), use the Subaru

Select Monitor to read the waveform data.

• At normal condition

• At abnormal condition 1 (numerous inversion)

• At abnormal condition 2 (noise input)

Is a normal waveform dis-

played?

Go to step 4. • The waveform is

displayed at abnor-

mal condition 1: Go

to step 4.

• The waveform is

displayed at abnor-

mal condition 2: Go

to step 5.

4 CHECK CATALYTIC CONVERTER. Is the catalytic converter dam-

aged?

Replace the cata-

lytic converter.

<Ref. to EX(w/o

STI)-35, Center

Exhaust Pipe.>

Go to step 5.

5 CHECK REAR OXYGEN SENSOR CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 6.

Step Check Yes No

EN-06668

10 sec/div

REAR OXYGEN

SENSOR VOLTAGE

(V)

EN-06669

10 sec/div

REAR OXYGEN

SENSOR VOLTAGE

(V)

EN-06670

10 sec/div

REAR OXYGEN

SENSOR VOLTAGE

(V)

15WRX_STI_US_EN.book 256 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-257

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

6 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 7. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

7 CHECK REAR OXYGEN SENSOR SHIELD.

1) Turn the ignition switch to OFF.

2) Expose the rear oxygen sensor connector

body side harness sensor shield.

3) Measure the resistance between sensor

shield and engine ground.

Is the resistance less than 1 Ω? Go to step 8. Repair the open

circuit of rear oxy-

gen sensor har-

ness.

8 CHECK ENGINE OIL AMOUNT AND EX-

HAUST GAS.

1) Check the engine oil amount. <Ref. to LU(w/

o STI)-10, INSPECTION, Engine Oil.>

2) Check exhaust gas during idling.

Does the engine oil amount

drop or white smoke emit from

the muffler?

Check the engine,

and repair the

defective part.

<Ref. to ME(w/o

STI)-352,

INSPECTION,

Engine Trouble in

General.>

After repairing the

engine, replace the

front catalytic con-

verter. <Ref. to

EX(w/o STI)-35,

Center Exhaust

Pipe.>

After the catalytic

converter is

replaced, perform

step 2 to check the

normal waveform

is displayed, and

then exit the proce-

dure.

Go to step 9.

9 CHECK IGNITION SYSTEM.

1) Check the spark plug. <Ref. to IG(w/o STI)-

8, INSPECTION, Spark Plug.>

2) Check the status of the ignition coil connec-

tor and the spark plug terminal.

Is there any fault in the ignition

system?

After repairing the

ignition system,

replace the front

catalytic con-

verter. <Ref. to

EX(w/o STI)-35,

Center Exhaust

Pipe.>

After the catalytic

converter is

replaced, perform

step 2 to check the

normal waveform

is displayed, and

then exit the proce-

dure.

Go to step 10.

Step Check Yes No

15WRX_STI_US_EN.book 257 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-258

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

10 CHECK FUEL SYSTEM.

1) Refer to and check the items in “Insufficient

fuel supply to fuel injector” (except for “a. Fuel

pump does not operate.”) and “Leakage or blow

out of fuel”. <Ref. to FU(w/o STI)-202, INSPEC-

TION, Fuel System Trouble in General.>

2) Check throttle body. <Ref. to FU(w/o STI)-

16, INSPECTION, Throttle Body.>

3) Check intake manifold. <Ref. to FU(w/o

STI)-42, INSPECTION, Intake Manifold.>

Is there any fault in the fuel sys-

tem?

After repairing the

fuel system,

replace the front

catalytic con-

verter. <Ref. to

EX(w/o STI)-35,

Center Exhaust

Pipe.>

After the catalytic

converter is

replaced, perform

step 2 to check the

normal waveform

is displayed, and

then exit the proce-

dure.

Go to step 11.

11 CHECK DTC. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

After checking the

DTC, replace the

front catalytic con-

verter. <Ref. to

EX(w/o STI)-35,

Center Exhaust

Pipe.>

After the catalytic

converter is

replaced, perform

step 2 to check the

normal waveform

is displayed, and

then exit the proce-

dure.

Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 258 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-259

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CW:DTC P0441 EVAPORATIVE EMISSION CONT. SYS. INCORRECT PURGE

FLOW

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-128, DTC P0441 EVAPORATIVE EMISSION CONT.

SYS. INCORRECT PURGE FLOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK PURGE CONTROL SOLENOID

VALVE.

Operate the purge control solenoid valve using

the Subaru Select Monitor.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

Does the purge control sole-

noid valve operate?

Go to step 3. Replace the purge

control solenoid

valve. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

3 CHECK EVAPORATIVE EMISSION CON-

TROL SYSTEM LINE.

Turn the ignition switch to OFF.

Are there holes, cracks, clog-

ging, or disconnection, miscon-

nection of hoses or pipes in

evaporative emission control

system?

Repair or replace

the hoses or pipes.

Repair the poor

contact of ECM

connector.

15WRX_STI_US_EN.book 259 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-260

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CX:DTC P0451 EVAPORATIVE EMISSION SYSTEM PRESSURE SENSOR/

SWITCH RANGE/PERFORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-130, DTC P0451 EVAPORATIVE EMISSION SYSTEM

PRESSURE SENSOR/SWITCH RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Cri-

teria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK CURRENT DATA.

1) Turn the ignition switch to ON (engine OFF).

2) Using the Subaru Select Monitor or general

scan tool, read the value in «Absolute Evap

Sys. Pressure» and «Mani. Absolute Pres-

sure», and compare them with the actual atmo-

spheric pressure.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

• To read the actual atmospheric pressure,

connect the Subaru Select Monitor or general

scan tool to the other known good vehicle.

Is the difference with the actual

atmospheric pressure 6.2 kPa

(46.5 mmHg, 1.83 inHg) or

more?

Replace the part

that showed larger

deviation from the

actual atmospheric

pressure than the

other.

• If deviations in

value for «Absolute

Evap Sys. Pres-

sure» is larger:

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

• If deviations in

value for «Mani.

Absolute Pres-

sure» is larger:

Replace the mani-

fold absolute pres-

sure and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-120, Mani-

fold Absolute Pres-

sure and Intake Air

Temperature Sen-

sor.>

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

15WRX_STI_US_EN.book 260 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-261

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CY:DTC P0452 EVAPORATIVE EMISSION SYSTEM PRESSURE SENSOR/

SWITCH LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-132, DTC P0452 EVAPORATIVE EMISSION SYSTEM

PRESSURE SENSOR/SWITCH LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B97

1234 56789

10 11 12 13 14 15 16 17 18 19 20

B122

EN-10808

R1B97

B122

J/C

R400

1234

5678

R400

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

B134

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BROWN)

VACUUM

PUMP

MAIN RELAY

BATTERY

FUSE HOLDER

LEAK CHECK VALVE ASSY

SWITCHING

VALVE

PRESSURE

SENSOR

: TERMINAL No. OPTIONAL ARRANGEMENT

15WRX_STI_US_EN.book 261 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-262

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Turn the ignition switch to ON.

2) Read the value of «Absolute Evap Sys.

Pressure» using the Subaru Select Monitor or a

general scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value in «Absolute Evap

Sys. Pressure» 34 kPa (255

mmHg, 10 inHg) or less?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK POWER SUPPLY OF LEAK CHECK

VALVE ASSEMBLY.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the leak

check valve assembly.

3) Turn the ignition switch to ON.

4) Measure the voltage between the leak

check valve assembly connector and chassis

ground.

Connector & terminal

(R400) No. 6 (+) — Chassis ground (–):

Is the voltage 4.5 V or more? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and the leak check

valve assembly

connector

• Poor contact of

ECM connector

• Poor contact of

coupling connector

3 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and chassis ground.

Connector & terminal

(B134) No. 15 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair the short

circuit to ground in

harness between

ECM connector

and leak check

valve assembly

connector.

4 CHECK FOR POOR CONTACT.

Check for poor contact of leak check valve

assembly connector.

Is there poor contact in the leak

check valve assembly connec-

tor?

Repair the poor

contact in the leak

check valve

assembly connec-

tor.

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

15WRX_STI_US_EN.book 262 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-263

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

CZ:DTC P0453 EVAPORATIVE EMISSION SYSTEM PRESSURE SENSOR/

SWITCH HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-133, DTC P0453 EVAPORATIVE EMISSION SYSTEM

PRESSURE SENSOR/SWITCH HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B97

1234 56789

10 11 12 13 14 15 16 17 18 19 20

B122

EN-10808

R1B97

B122

J/C

R400

1234

5678

R400

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

B134

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BROWN)

VACUUM

PUMP

MAIN RELAY

BATTERY

FUSE HOLDER

LEAK CHECK VALVE ASSY

SWITCHING

VALVE

PRESSURE

SENSOR

: TERMINAL No. OPTIONAL ARRANGEMENT

15WRX_STI_US_EN.book 263 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-264

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Turn the ignition switch to ON.

2) Read the value of «Absolute Evap Sys.

Pressure» using the Subaru Select Monitor or a

general scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value in «Absolute Evap

Sys. Pressure» 125 kPa (938

mmHg, 36.9 inHg) or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the leak check valve assembly.

3) Measure the resistance of harness between

ECM connector and the leak check valve

assembly connector.

Connector & terminal

(B134) No. 15 — (R400) No. 7:

(B134) No. 19 — (R400) No. 8:

Is the resistance less than 1 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and the leak check

valve assembly

connector

• Poor contact of

coupling connector

• Poor contact of

joint connector

3 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and the leak

check valve assembly connector.

Is there poor contact in ECM

and the leak check valve

assembly connector?

Repair the poor

contact of ECM

and the leak check

valve assembly

connector.

Go to step 4.

4 CHECK LEAK CHECK VALVE ASSEMBLY.

Check the pressure sensor of the leak check

valve assembly. <Ref. to EC(w/o STI)-70,

CHECK PRESSURE SENSOR, INSPECTION,

Leak Check Valve Assembly.>

Is the pressure sensor of the

leak check valve assembly OK?

Repair the short

circuit to power in

harness between

ECM connector

and leak check

valve assembly

connector.

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

15WRX_STI_US_EN.book 264 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-265

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DA:DTC P0455 EVAPORATIVE EMISSION SYSTEM LEAK DETECTED (LARGE

LEAK)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-134, DTC P0455 EVAPORATIVE EMISSION SYSTEM

LEAK DETECTED (LARGE LEAK), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Fuel odor

• There is a hole of more than 1.0 mm (0.04 in) dia. in evaporation system or fuel tank.

• Fuel filler cap loose or lost

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FUEL FILLER CAP.

1) Turn the ignition switch to OFF.

2) Check the fuel filler cap.

NOTE:

The DTC is stored in memory if fuel filler cap is

or was loose or if the cap chain has caught while

tightening.

Is the fuel filler cap tightened

securely?

Go to step 2. Tighten fuel filler

cap securely.

2 CHECK FUEL FILLER CAP. Is the fuel filler cap genuine? Go to step 3. Replace with a

genuine fuel filler

cap.

3 CHECK FUEL FILLER PIPE GASKET. Is there any damage to the seal

between fuel filler cap and fuel

filler pipe?

Repair or replace

the fuel filler cap

and fuel filler pipe.

<Ref. to FU(w/o

STI)-163, Fuel

Filler Pipe.>

Go to step 4.

4 CHECK PURGE CONTROL SOLENOID

VALVE.

Check air-tightness of the purge control sole-

noid valve. <Ref. to EC(w/o STI)-29, INSPEC-

TION, Purge Control Solenoid Valve.>

Is the purge control solenoid

valve OK?

Go to step 5. Replace the purge

control solenoid

valve. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

5 CHECK EVAPORATIVE EMISSION CON-

TROL SYSTEM LINE.

Are there holes on the evapora-

tion line?

Repair or replace

the evaporation

line. <Ref. to FU(w/

o STI)-194, Fuel

Delivery and Evap-

oration Lines.>

Go to step 6.

6 CHECK CANISTER. Are there holes on the canis-

ter?

Replace the canis-

ter. <Ref. to EC(w/

o STI)-8, Canis-

ter.>

Go to step 7.

7 CHECK LEAK CHECK VALVE ASSEMBLY. Are there damage or holes on

the leak check valve assembly?

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

Go to step 8.

8 CHECK FUEL TANK.

Remove the fuel tank. <Ref. to FU(w/o STI)-

152, Fuel Tank.>

Are there damage or holes on

the fuel tank?

Repair or replace

the fuel tank. <Ref.

to FU(w/o STI)-

152, Fuel Tank.>

Go to step 9.

15WRX_STI_US_EN.book 265 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-266

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DB:DTC P0456 EVAPORATIVE EMISSION CONTROL SYSTEM LEAK DETECT-

ED (VERY SMALL LEAK)

NOTE:

For the diagnostic procedure, refer to DTC P0455. <Ref. to EN(w/o STI)(diag)-265, DTC P0455 EVAPORA-

TIVE EMISSION SYSTEM LEAK DETECTED (LARGE LEAK), Diagnostic Procedure with Diagnostic Trou-

ble Code (DTC).>

9 CHECK ANY OTHER MECHANICAL TROU-

BLE IN EVAPORATIVE EMISSION CON-

TROL SYSTEM.

Are there holes, cracks, clog-

ging, or disconnection, miscon-

nection of hoses or pipes in

evaporative emission control

system?

Repair or replace

the hoses or pipes.

Repair the poor

contact of ECM

connector.

Step Check Yes No

15WRX_STI_US_EN.book 266 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-267

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DC:DTC P0458 EVAPORATIVE EMISSION SYSTEM PURGE CONTROL VALVE

CIRCUIT LOW

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-140, DTC P0458 EVAPORATIVE EMISSION SYSTEM

PURGE CONTROL VALVE CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK OUTPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 4 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

17 18

25 26

19 20

27 28

E159

E52

B22

EN-10809

B550

215

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E159

E52

212

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

PURGE CONTROL

SOLENOID VALVE 1

PURGE CONTROL

SOLENOID VALVE 2

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 267 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-268

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

3 CHECK POWER SUPPLY TO PURGE CON-

TROL SOLENOID VALVE 1 CONNECTOR.

Measure the voltage between purge control

solenoid valve 1 connector and engine ground.

Connector & terminal

(E4) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 1

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

purge control solenoid valve 1.

3) Measure the resistance between the purge

control solenoid valve 1 connector and engine

ground.

Connector & terminal

(E4) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the ground

short circuit of har-

ness between

ECM connector

and purge control

solenoid valve 1

connector.

5 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 1

CONNECTOR.

Measure the resistance of harness between

ECM connector and purge control solenoid

valve 1 connector.

Connector & terminal

(E159) No. 4 — (E4) No. 2:

Is the resistance less than 1 Ω? Go to step 6. Repair the open

circuit in harness

between ECM con-

nector and purge

control solenoid

valve 1 connector.

6 CHECK PURGE CONTROL SOLENOID

VALVE 1.

1) Remove the purge control solenoid valve 1.

2) Measure the resistance between purge con-

trol solenoid valve 1 terminals.

Terminals

No. 1 — No. 2:

Is the resistance 10 — 100 Ω? Repair the poor

contact of the

purge control sole-

noid valve 1 con-

nector.

Replace the purge

control solenoid

valve 1. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

Step Check Yes No

15WRX_STI_US_EN.book 268 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-269

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DD:DTC P0459 EVAPORATIVE EMISSION SYSTEM PURGE CONTROL VALVE

CIRCUIT HIGH

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-141, DTC P0459 EVAPORATIVE EMISSION SYSTEM

PURGE CONTROL VALVE CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 1

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

purge control solenoid valve 1.

3) Turn the ignition switch to ON.

4) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 4 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

harness between

ECM connector

and purge control

solenoid valve 1

connector.

Go to step 2.

17 18

25 26

19 20

27 28

E159

E52

B22

EN-10809

B550

215

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E159

E52

212

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

PURGE CONTROL

SOLENOID VALVE 1

PURGE CONTROL

SOLENOID VALVE 2

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 269 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-270

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK PURGE CONTROL SOLENOID

VALVE 1.

1) Turn the ignition switch to OFF.

2) Measure the resistance between purge con-

trol solenoid valve 1 terminals.

Terminals

No. 1 — No. 2:

Is the resistance less than 1 Ω? Replace the purge

control solenoid

valve 1. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

Repair the poor

contact of ECM

connector.

Step Check Yes No

15WRX_STI_US_EN.book 270 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-271

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DE:DTC P0461 FUEL LEVEL SENSOR “A” CIRCUIT RANGE/PERFORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-142, DTC P0461 FUEL LEVEL SENSOR “A” CIRCUIT

RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

DF:DTC P0462 FUEL LEVEL SENSOR “A” CIRCUIT LOW

NOTE:

For the diagnostic procedure, refer to DTC P0463. <Ref. to EN(w/o STI)(diag)-272, DTC P0463 FUEL LEV-

EL SENSOR “A” CIRCUIT HIGH, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Replace the fuel

level sensor and

fuel sub level sen-

sor. <Ref. to FU(w/

o STI)-173, Fuel

Level Sensor.>

<Ref. to FU(w/o

STI)-176, Fuel Sub

Level Sensor.>

15WRX_STI_US_EN.book 271 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-272

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DG:DTC P0463 FUEL LEVEL SENSOR “A” CIRCUIT HIGH

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-144, DTC P0463 FUEL LEVEL SENSOR “A” CIRCUIT

HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

DH:DTC P0500 VEHICLE SPEED SENSOR “A”

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-145, DTC P0500 VEHICLE SPEED SENSOR “A”, Diag-

nostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is DTC P0462 or P0463 dis-

played on the Subaru Select

Monitor?

Check the combi-

nation meter. <Ref.

to IDI(diag)-2,

Basic Diagnostic

Procedure.>

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

Step Check Yes No

1 CHECK DTC OF VDC.

Check DTC of VDC.

Is DTC of VDC displayed? Perform the diag-

nosis according to

DTC. <Ref. to

VDC(diag)-42, List

of Diagnostic Trou-

ble Code (DTC).>

Repair the poor

contact of ECM

connector.

15WRX_STI_US_EN.book 272 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-273

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DI: DTC P0506 IDLE AIR CONTROL SYSTEM RPM LOWER THAN EXPECTED

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-146, DTC P0506 IDLE AIR CONTROL SYSTEM RPM

LOWER THAN EXPECTED, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Hard to start the engine.

• Engine does not start.

• Improper idling

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK AIR CLEANER ELEMENT.

1) Turn the ignition switch to OFF.

2) Check the air cleaner element.

Is there excessive clogging on

air cleaner element?

Replace the air

cleaner element.

<Ref. to IN(w/o

STI)-7, Air Cleaner

Element.>

Go to step 3.

3 CHECK ELECTRONIC THROTTLE CON-

TROL.

1) Remove the electronic throttle control. <Ref.

to FU(w/o STI)-15, REMOVAL, Throttle Body.>

2) Check the electronic throttle control.

Are foreign matter found inside

electronic throttle control?

Remove foreign

matter from elec-

tronic throttle con-

trol.

Perform the diag-

nosis of DTC

P2101. <Ref. to

EN(w/o STI)(diag)-

423, DTC P2101

THROTTLE

ACTUATOR CON-

TROL MOTOR

CIRCUIT RANGE/

PERFORMANCE,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).>

15WRX_STI_US_EN.book 273 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-274

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DJ:DTC P0507 IDLE AIR CONTROL SYSTEM RPM HIGHER THAN EXPECTED

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-147, DTC P0507 IDLE AIR CONTROL SYSTEM RPM

HIGHER THAN EXPECTED, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Engine keeps running at higher speed than specified idle speed.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK AIR INTAKE SYSTEM.

1) Start and idle the engine.

2) Check the following items.

• Loose installation of intake manifold and

throttle body

• Cracks of intake manifold gasket and throttle

body gasket

• Disconnection of vacuum hoses

Is there any fault in air intake

system?

Repair air suction

and leaks.

Go to step 3.

3 CHECK ELECTRONIC THROTTLE CON-

TROL.

1) Turn the ignition switch to OFF.

2) Remove the electronic throttle control. <Ref.

to FU(w/o STI)-15, REMOVAL, Throttle Body.>

3) Check the electronic throttle control.

Are foreign matter found inside

electronic throttle control?

Remove foreign

matter from elec-

tronic throttle con-

trol.

Perform the diag-

nosis of DTC

P2101. <Ref. to

EN(w/o STI)(diag)-

423, DTC P2101

THROTTLE

ACTUATOR CON-

TROL MOTOR

CIRCUIT RANGE/

PERFORMANCE,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).>

15WRX_STI_US_EN.book 274 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-275

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DK:DTC P050A COLD START IDLE AIR CONTROL SYSTEM PERFORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-148, DTC P050A COLD START IDLE AIR CONTROL

SYSTEM PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine keeps running at higher speed than specified idle speed.

• Engine keeps running at a lower speed than the specified idle speed.

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 275 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-276

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 276 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-277

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK ENGINE OIL. Is there a proper amount of

engine oil?

Go to step 3. Replace engine oil.

<Ref. to LU(w/o

STI)-11,

REPLACEMENT,

Engine Oil.>

3 CHECK EXHAUST SYSTEM. Are there holes or loose bolts

on exhaust system?

Repair the exhaust

system.

Go to step 4.

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 277 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-278

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

4 CHECK AIR INTAKE SYSTEM. Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

Go to step 5.

5 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 328 —

358 kPa (3.3 — 3.7 kgf/cm

, 48

— 52 psi)?

Go to step 6. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

6 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

1) Start the engine and warm up completely.

2) Read the value of «Coolant Temp.» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Coolant Temp.»

75°C (167°F) or more?

Go to step 7. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

7 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Read the value of «Mass Air Flow» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Mass Air

Flow» 2.0 — 5.0 g/s (0.26 —

0.66 lb/m)?

Go to step 8. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 278 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-279

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

8 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Open the front hood.

6) Measure the ambient temperature.

7) Read the value of «IAT Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Subtract ambient temperature

value from the value of «IAT

Sensor #11». Is the obtained

value –10 — 50°C (–18 —

90°F)?

Go to step 9. Check the mass air

flow and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-118, Mass

Air Flow and Intake

Air Temperature

Sensor.>

9 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from fuel injector

on faulty cylinders.

3) Measure the resistance between fuel injec-

tor connector and engine ground on faulty cylin-

ders.

Connector & terminal

#1 (E5) No. 1 — Engine ground:

#1 (E5) No. 2 — Engine ground:

#2 (E16) No. 1 — Engine ground:

#2 (E16) No. 2 — Engine ground:

#3 (E6) No. 1 — Engine ground:

#3 (E6) No. 2 — Engine ground:

#4 (E17) No. 1 — Engine ground:

#4 (E17) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 10. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

10 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance of harness between

ECM and fuel injector connector on faulty cylin-

ders.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 11. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

11 CHECK FUEL INJECTOR.

Check the fuel injector on faulty cylinder. <Ref.

to FU(w/o STI)-70, INSPECTION, Fuel Injec-

tor.>

Are fuel injectors OK? Go to step 12. Replace the faulty

fuel injector. <Ref.

to FU(w/o STI)-51,

Fuel Injector.>

Step Check Yes No

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EN(w/o STI)(diag)-280

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

12 CHECK INSTALLATION CONDITION OF

CAMSHAFT POSITION SENSOR/CRANK-

SHAFT POSITION SENSOR.

Is the camshaft position sensor

or crankshaft position sensor

loosely installed?

Tighten the cam-

shaft position sen-

sor or crankshaft

position sensor.

<Ref. to FU(w/o

STI)-104, INSTAL-

LATION, Cam-

shaft Position

Sensor.> <Ref. to

FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

Go to step 13.

13 CHECK CRANKSHAFT POSITION SENSOR

PLATE.

Is the crankshaft position sen-

sor plate rusted or does it have

broken teeth?

Replace the crank-

shaft position sen-

sor plate. <Ref. to

ME(w/o STI)-260,

Cylinder Block.>

Go to step 14.

14 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Turn the crankshaft using ST, and align the

alignment mark on crank sprocket with align-

ment mark on cylinder block.

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain dislocated

from its proper position?

Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

Go to step 15.

15 CHECK ELECTRONIC THROTTLE CON-

TROL RELAY.

1) Turn the ignition switch to OFF.

2) Remove the electronic throttle control relay.

3) Connect the battery to terminals No. 16 and

No. 17 of electronic throttle control relay.

4) Measure the resistance between electronic

throttle control relay terminals.

Terminals

No. 14 — No. 15:

Is the resistance less than 1 Ω? Go to step 16. Replace the elec-

tronic throttle con-

trol relay. <Ref. to

FU(w/o STI)-139,

Electronic Throttle

Control Relay.>

16 CHECK POWER SUPPLY OF ELECTRONIC

THROTTLE CONTROL RELAY.

Measure the voltage between electronic throttle

control relay connector and chassis ground.

Connector & terminal

(B225) No. 15 (+) — Chassis ground (–):

Is the voltage 10 V or more? Go to step 17. Repair the open or

ground short circuit

of power supply

circuit.

17 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

1) Disconnect the connector from ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between electronic

throttle control relay connector and chassis

ground.

Connector & terminal

(B225) No. 17 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control relay con-

nector.

Go to step 18.

Step Check Yes No

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EN(w/o STI)(diag)-281

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

18 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

1) Turn the ignition switch to OFF.

2) Measure the resistance between electronic

throttle control relay connector and chassis

ground.

Connector & terminal

(B225) No. 14 — Chassis ground:

(B225) No. 17 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 19. Repair the short

circuit to ground in

harness between

ECM connector

and electronic

throttle control

relay connector.

19 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

Measure the resistance between ECM connec-

tor and electronic throttle control relay connec-

tor.

Connector & terminal

(B134) No. 39 — (B225) No. 17:

(B134) No. 11 — (B225) No. 14:

Is the resistance less than 1 Ω? Go to step 20. Repair the open

circuit in harness

between ECM con-

nector and elec-

tronic throttle

control relay con-

nector.

20 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from electronic

throttle control.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 18 — Engine ground:

(E158) No. 17 — Engine ground:

(E158) No. 29 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 21. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

21 CHECK SHORT CIRCUIT INSIDE THE ECM.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 1 — Engine ground:

(E57) No. 4 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 22. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

Replace the ECM if

defective. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

22 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance of harness between

ECM connector and electronic throttle control

connector.

Connector & terminal

(E158) No. 17 — (E57) No. 1:

(E158) No. 30 — (E57) No. 3:

(E158) No. 29 — (E57) No. 4:

Is the resistance less than 1 Ω? Go to step 23. Repair the open

circuit of harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Step Check Yes No

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EN(w/o STI)(diag)-282

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

23 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 3 — Engine ground:

Is the resistance less than 5 Ω? Go to step 24. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

ECM connector

• Poor contact of

coupling connector

24 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 1 (+) — Engine ground (–):

(E57) No. 4 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Go to step 25.

25 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 18 — (E158) No. 17:

(E158) No. 18 — (E158) No. 29:

Is the resistance 1 MΩ or

more?

Go to step 26. Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

26 CHECK SENSOR OUTPUT.

1) Connect all connectors.

2) Turn the ignition switch to ON.

3) Read the value of «Main-Throttle Sensor»

using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «Main-Throttle

Sensor» 0.60 — 0.65 V?

Go to step 27. Repair the poor

contact of elec-

tronic throttle con-

trol connector.

Replace the elec-

tronic throttle con-

trol if defective.

<Ref. to FU(w/o

STI)-15, Throttle

Body.>

27 CHECK SENSOR OUTPUT.

Read the value of «Sub-Throttle Sensor» using

Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «Sub-Throttle

Sensor» 0.60 — 0.65 V?

Go to step 28. Repair the poor

contact of elec-

tronic throttle con-

trol connector.

Replace the elec-

tronic throttle con-

trol if defective.

<Ref. to FU(w/o

STI)-15, Throttle

Body.>

Step Check Yes No

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EN(w/o STI)(diag)-283

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

28 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL MO-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

electronic throttle control.

3) Measure the resistance between ECM con-

nector and electronic throttle control connector.

Connector & terminal

(E159) No. 1 — (E57) No. 5:

(E159) No. 2 — (E57) No. 6:

Is the resistance less than 1 Ω? Go to step 29. Repair the open

circuit of harness

between ECM con-

nector and elec-

tronic throttle

control.

29 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL MO-

TOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 5 (+) — Engine ground (–):

(E57) No. 6 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Go to step 30.

30 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL MO-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 5 — Engine ground:

(E57) No. 6 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 31. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

31 CHECK ELECTRONIC THROTTLE CON-

TROL MOTOR HARNESS.

Measure the resistance between electronic

throttle control connectors.

Connector & terminal

(E57) No. 5 — (E57) No. 6:

Is the resistance 1 MΩ or

more?

Go to step 32. Repair the short

circuit in harness

between ECM con-

nector and elec-

tronic throttle

control connector.

32 CHECK ELECTRONIC THROTTLE CON-

TROL GROUND CIRCUIT.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(B134) No. 35 — Engine ground:

(B134) No. 47 — Engine ground:

(E159) No. 10 — Engine ground:

(E159) No. 17 — Engine ground:

(E159) No. 18 — Engine ground:

(E159) No. 25 — Engine ground:

(E159) No. 26 — Engine ground:

Is the resistance less than 5 Ω? Go to step 33. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

coupling connector

33 CHECK ELECTRONIC THROTTLE CON-

TROL.

Measure the resistance between electronic

throttle control terminals.

Terminals

No. 5 — No. 6:

Is the resistance 50 Ω or less? Go to step 34. Replace the elec-

tronic throttle con-

trol. <Ref. to FU(w/

o STI)-15, Throttle

Body.>

Step Check Yes No

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EN(w/o STI)(diag)-284

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DL:DTC P050B COLD START IGNITION TIMING PERFORMANCE

NOTE:

For the diagnostic procedure, refer to DTC P050A. <Ref. to EN(w/o STI)(diag)-275, DTC P050A COLD

START IDLE AIR CONTROL SYSTEM PERFORMANCE, Diagnostic Procedure with Diagnostic Trouble

Code (DTC).>

34 CHECK ELECTRONIC THROTTLE CON-

TROL.

Move the throttle valve to the fully open and fully

closed positions with fingers.

Check that the valve returns to the specified

position when releasing fingers.

Does the valve return to the

specified position? Standard

value: 3 mm (0.12 in) from fully

closed position

Repair the poor

contact of ECM

connector.

Replace the elec-

tronic throttle con-

trol. <Ref. to FU(w/

o STI)-15, Throttle

Body.>

Step Check Yes No

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EN(w/o STI)(diag)-285

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DM:DTC P0512 STARTER REQUEST CIRCUIT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-150, DTC P0512 STARTER REQUEST CIRCUIT, Diag-

nostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

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EN(w/o STI)(diag)-286

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

CVT

B23

12345

6789

CVT

721

B12

B134

B14

B574C:

B572A:

B576B575

B106

B225

39 38

B225

B106

B550

923

B225

PRND

B12

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

19 20 21 22 23 24 25 26 27 28 29 30

789

10 11 12 13 14 15 16 17 18

123 456

B574C:

11 12

13 14

15 16

17 18

B572A:

B575

123

456789

10 11

12 13 14 15 16 17 18 19 20 21 22

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10791

B14

B23 B28

B550

822

232221 262524201918

587

10 11

B550

SBF-6

ECM

FUSE

HOLDER

(BROWN)

INHIBITOR

SWITCH

STARTER

CUT

RELAY

FUSE HOLDER

BATTERY

MAIN SBF

IG RELAY 1

(PUSH BUTTON

START)

F/B No. 26

STARTER RELAY

(PUSH BUTTON START)

STARTER

RELAY 1

CLUTCH

START

SWITCH

F/B No. 21

KEYLESS

ACCESS CM

STARTER MOTOR

15WRX_STI_US_EN.book 286 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-287

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK PUSH BUTTON IGNITION SWITCH.

Operate the push button ignition switch.

Does it operate smoothly with-

out catch?

Go to step 2. Replace the push

button ignition

switch. <Ref. to

SL-106, Push But-

ton Ignition

Switch.>

2 CHECK DTC.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, Clear Memory Mode.>

2) Start and idle the engine for three minutes

or more.

Is the same DTC as current

diagnosis output?

Go to step 3. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

3 CHECK HARNESS BETWEEN ECM AND

KEYLESS ACCESS CM.

1) Turn the ignition to OFF.

2) Disconnect the connector from ECM.

3) Turn the ignition to ON.

4) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 45 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power

supply in harness

between ECM con-

nector and keyless

access CM con-

nector.

Repair the poor

contact of ECM

connector.

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EN(w/o STI)(diag)-288

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DN:DTC P0560 SYSTEM VOLTAGE

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-151, DTC P0560 SYSTEM VOLTAGE, Diagnostic Trou-

ble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B72

B550

923

B225

36 37

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B550

215

B220

B134A:

E159C:

A32

A23

A38

A24

A12

B220 B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10792

C25

C26

B22

A47

A35

C10

C17

C18

B72

7856

3412

ECM

SBF-7

SBF-6

232221 262524201918

587

10 11

B550

: WITHOUT PUSH BUTTON START

: WITH PUSH BUTTON START

BATTERY

MAIN

RELAY

FUSE HOLDER

M/B No. 13

F/B No. 12

(BROWN)

(GRAY)

IG RELAY 1

(PUSH BUTTON

START)

FUSE HOLDER

IGNITION

SWITCH

MAIN SBF

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EN(w/o STI)(diag)-289

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK INPUT SIGNAL OF ECM.

1) Turn the ignition switch to OFF.

2) Measure the voltage between ECM connec-

tor and chassis ground.

Connector & terminal

(B134) No. 23 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the poor

contact of ECM

connector.

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

MAIN FUSE BOX CONNECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance between ECM con-

nector and chassis ground.

Connector & terminal

(B134) No. 23 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 3. Repair the short

circuit to ground in

harness between

ECM connector

and battery termi-

nal.

3 CHECK FUSE NO. 13 (MAIN FUSE BOX). Is the fuse blown out? Replace the fuse. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and battery

• Poor contact of

ECM connector

• Poor contact of

battery terminal

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EN(w/o STI)(diag)-290

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DO:DTC P0604 INTERNAL CONTROL MODULE RANDOM ACCESS MEMORY

(RAM) ERROR

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-152, DTC P0604 INTERNAL CONTROL MODULE

RANDOM ACCESS MEMORY (RAM) ERROR, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine does not start.

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

DP:DTC P0605 INTERNAL CONTROL MODULE READ ONLY MEMORY (ROM)

ERROR

NOTE:

For the diagnostic procedure, refer to DTC P0606. <Ref. to EN(w/o STI)(diag)-291, DTC P0606 CONTROL

MODULE PROCESSOR, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

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EN(w/o STI)(diag)-291

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DQ:DTC P0606 CONTROL MODULE PROCESSOR

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-154, DTC P0606 CONTROL MODULE PROCESSOR,

Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10810

A12

A24

10 11

B220

15 2

B550

C25

C26

B22

A47

A35

C10

C17

C18

B30

B18

B29

B17

E57

232221 262524201918

587

10 11

B550

SBF-7

ECM

ELECTRONIC

THROTTLE

CONTROL

FUSE HOLDER

MAIN RELAY

BATTERY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 291 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-292

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DR:DTC P060A INTERNAL CONTROL MODULE MONITORING PROCESSOR

PERFORMANCE

NOTE:

For the diagnostic procedure, refer to DTC P0606. <Ref. to EN(w/o STI)(diag)-291, DTC P0606 CONTROL

MODULE PROCESSOR, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

DS:DTC P060B INTERNAL CONTROL MODULE A/D PROCESSING PERFOR-

MANCE

NOTE:

For the diagnostic procedure, refer to DTC P0606. <Ref. to EN(w/o STI)(diag)-291, DTC P0606 CONTROL

MODULE PROCESSOR, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

Step Check Yes No

1 CHECK INPUT VOLTAGE OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 12 (+) — Engine ground (–):

(B134) No. 24 (+) — Engine ground (–):

Is the voltage 10 — 13 V? Go to step 2. Repair the open or

ground short circuit

of power supply

circuit.

2 CHECK INPUT VOLTAGE OF ECM.

1) Start the engine.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 12 (+) — Engine ground (–):

(B134) No. 24 (+) — Engine ground (–):

Is the voltage 13 — 15 V? Go to step 3. Repair the open or

ground short circuit

of power supply

circuit.

3 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

electronic throttle control.

3) Measure the resistance of harness between

ECM connector and electronic throttle control

connector.

Connector & terminal

(E158) No. 18 — (E57) No. 2:

(E158) No. 30 — (E57) No. 3:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit of harness

between ECM con-

nector and elec-

tronic throttle

control connector.

4 CHECK ECM GROUND HARNESS.

1) Connect all connectors.

2) Turn the ignition to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 35 (+) — Engine ground (–):

(B134) No. 47 (+) — Engine ground (–):

(E159) No. 10 (+) — Engine ground (–):

(E159) No. 17 (+) — Engine ground (–):

(E159) No. 18 (+) — Engine ground (–):

(E159) No. 25 (+) — Engine ground (–):

(E159) No. 26 (+) — Engine ground (–):

Is the voltage less than 1 V? Check the connec-

tor for poor contact

and check the har-

ness. Replace the

ECM if no fault is

found. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

ground circuit

• Loose engine

ground terminal

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 292 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-293

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DT:DTC P0616 STARTER RELAY CIRCUIT LOW

1. MODEL WITHOUT PUSH BUTTON START

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-157, DTC P0616 STARTER RELAY CIRCUIT LOW, Di-

agnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, ENGINE

TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B72

7856

3412

CVT

21 7

B550

B134

B106

B12

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B14

EN-10818

CVT

B225

B14

DNRP

T3B12

CVT

B106

B72

232221 262524201918

587

10 11

B550

SBF-6

ECM

BATTERY

IGNITION

SWITCH

F/B No. 21

MAIN SBF

CLUTCH START SWITCH

INHIBITOR SWITCH

STARTER MOTOR

STARTER

RELAY 1

(BROWN)

FUSE HOLDER

15WRX_STI_US_EN.book 293 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-294

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2. MODEL WITH PUSH BUTTON START

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-157, DTC P0616 STARTER RELAY CIRCUIT LOW, Di-

agnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

STARTER RELAY CONNECTOR.

1) Turn the ignition switch to OFF.

2) Remove the starter relay.

3) Disconnect the connectors from ECM and

starter motor.

4) Measure the resistance of harness between

ECM connector and starter relay connector.

Connector & terminal

(B134) No. 8 — (B225) No. 1:

NOTE:

For CVT model, place the select lever in “P”

range or “N” range.

Is the resistance less than 1 Ω? Go to step 3.NOTE:

Check the follow-

ing item and repair

or replace if neces-

sary.

• Open circuit of

harness between

ECM connector

and starter relay

connector

• Poor contact of

coupling connector

3 CHECK HARNESS BETWEEN ECM AND

STARTER RELAY CONNECTOR.

Measure the resistance between ECM connec-

tor and chassis ground.

Connector & terminal

(B134) No. 8 — Chassis ground:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of ECM

connector.

Repair the short

circuit to ground in

harness between

ECM connector

and starter relay

connector.

15WRX_STI_US_EN.book 294 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-295

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

CVT

B23

12345

6789

CVT

721

B12

B134

B14

B574C:

B572A:

B576B575

B106

B225

39 38

B225

B106

B550

923

B225

PRND

B12

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

19 20 21 22 23 24 25 26 27 28 29 30

789

10 11 12 13 14 15 16 17 18

123 456

B574C:

11 12

13 14

15 16

17 18

B572A:

B575

123

456789

10 11

12 13 14 15 16 17 18 19 20 21 22

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10791

B14

B23 B28

B550

822

232221 262524201918

587

10 11

B550

SBF-6

ECM

FUSE

HOLDER

(BROWN)

INHIBITOR

SWITCH

STARTER

CUT

RELAY

FUSE HOLDER

BATTERY

MAIN SBF

IG RELAY 1

(PUSH BUTTON

START)

F/B No. 26

STARTER RELAY

(PUSH BUTTON START)

STARTER

RELAY 1

CLUTCH

START

SWITCH

F/B No. 21

KEYLESS

ACCESS CM

STARTER MOTOR

15WRX_STI_US_EN.book 295 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-296

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

STARTER RELAY CONNECTOR.

1) Turn the ignition to OFF.

2) Disconnect the connector from ECM.

3) Remove the starter relay.

4) Measure the resistance of harness between

ECM connector and starter relay connector.

NOTE:

For CVT model, place the select lever in “P”

range or “N” range.

Connector & terminal

(B134) No. 8 — (B225) No. 1:

Is the resistance less than 1 Ω? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and starter relay

connector

• Poor contact of

coupling connector

2 CHECK HARNESS BETWEEN ECM AND

STARTER RELAY CONNECTOR.

1) Disconnect the connector from starter

motor.

2) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 8 — Engine ground:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of ECM

connector.

Repair the short

circuit to ground in

harness between

ECM connector

and starter relay

connector.

15WRX_STI_US_EN.book 296 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-297

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DU:DTC P0617 STARTER RELAY CIRCUIT HIGH

1. MODEL WITHOUT PUSH BUTTON START

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-158, DTC P0617 STARTER RELAY CIRCUIT HIGH, Di-

agnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, ENGINE

TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B72

7856

3412

CVT

21 7

B550

B134

B106

B12

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B14

EN-10818

CVT

B225

B14

DNRP

T3B12

CVT

B106

B72

232221 262524201918

587

10 11

B550

SBF-6

ECM

BATTERY

IGNITION

SWITCH

F/B No. 21

MAIN SBF

CLUTCH START SWITCH

INHIBITOR SWITCH

STARTER MOTOR

STARTER

RELAY 1

(BROWN)

FUSE HOLDER

15WRX_STI_US_EN.book 297 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-298

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2. MODEL WITH PUSH BUTTON START

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-158, DTC P0617 STARTER RELAY CIRCUIT HIGH, Di-

agnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

STARTER RELAY CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Turn the ignition switch to ON.

4) Measure the voltage between ECM connec-

tor and chassis ground.

Connector & terminal

(B134) No. 8 (+) — Chassis ground (–):

NOTE:

For CVT model, place the select lever in “P”

range or “N” range.

Is the voltage 10 V or more? Repair the short

circuit to power in

harness between

ECM connector

and starter relay

connector.

Repair the poor

contact of ECM

connector.

15WRX_STI_US_EN.book 298 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-299

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

CVT

B23

12345

6789

CVT

721

B12

B134

B14

B574C:

B572A:

B576B575

B106

B225

39 38

B225

B106

B550

923

B225

PRND

B12

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

19 20 21 22 23 24 25 26 27 28 29 30

789

10 11 12 13 14 15 16 17 18

123 456

B574C:

11 12

13 14

15 16

17 18

B572A:

B575

123

456789

10 11

12 13 14 15 16 17 18 19 20 21 22

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10791

B14

B23 B28

B550

822

232221 262524201918

587

10 11

B550

SBF-6

ECM

FUSE

HOLDER

(BROWN)

INHIBITOR

SWITCH

STARTER

CUT

RELAY

FUSE HOLDER

BATTERY

MAIN SBF

IG RELAY 1

(PUSH BUTTON

START)

F/B No. 26

STARTER RELAY

(PUSH BUTTON START)

STARTER

RELAY 1

CLUTCH

START

SWITCH

F/B No. 21

KEYLESS

ACCESS CM

STARTER MOTOR

15WRX_STI_US_EN.book 299 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-300

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK STARTER MOTOR.

1) Turn the ignition to ON.

2) Check the starter motor condition.

Is the starter motor rotating? Go to step 2. Repair the short

circuit to power

supply.

NOTE:

In this case, repair

the following har-

nesses:

• Short circuit to

power supply in

harness between

ECM connector

and starter relay

connector

• Short circuit to

power supply in

harness between

ECM connector

and starter motor

• Short circuit to

power supply in

harness between

starter relay con-

nector and starter

motor

2 CHECK HARNESS BETWEEN STARTER

CUT RELAY CONNECTOR AND STARTER

RELAY CONNECTOR.

1) Turn the ignition to OFF.

2) Disconnect the connector from starter

motor.

3) Remove the starter cut relay and starter

relay.

4) Turn the ignition to ON.

5) Measure the voltage between starter relay

connector and chassis ground.

Connector & terminal

(B225) No. 2 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power

supply in harness

between starter cut

relay connector

and starter relay

connector.

Go to step 3.

3 CHECK STARTER CUT RELAY.

1) Connect the battery to starter cut relay ter-

minals No. 40 and No. 42.

2) Measure the resistance between starter cut

relay terminals.

Terminals

No. 41 — No. 44:

Is the resistance 1 MΩ or

more?

Go to step 6. Replace the starter

cut relay. <Ref. to

SL-116, Starter

Cut Relay.>

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND

STARTER RELAY CONNECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 14 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and starter relay

connector.

5 CHECK STARTER RELAY.

Measure the resistance between starter relay

terminals.

Terminals

No. 1 — No. 2:

Is the resistance 1 MΩ or

more?

Go to step 6. Replace the starter

relay. <Ref. to

EN(w/o STI)(diag)-

9, LOCATION,

Electrical Compo-

nent Location.>

15WRX_STI_US_EN.book 300 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-301

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

6 CHECK HARNESS BETWEEN ECM, START-

ER RELAY CONNECTOR AND STARTER

MOTOR.

1) Disconnect the connector from ECM.

2) Turn the ignition to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 8 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power

supply.

NOTE:

In this case, repair

the following har-

nesses:

• Short circuit to

power supply in

harness between

ECM connector

and starter relay

connector

• Short circuit to

power supply in

harness between

ECM connector

and starter motor

• Short circuit to

power supply in

harness between

starter relay con-

nector and starter

motor

Repair the poor

contact of ECM

connector.

Step Check Yes No

15WRX_STI_US_EN.book 301 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-302

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DV:DTC P062D FUEL INJECTOR DRIVER CIRCUIT PERFORMANCE (BANK 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-159, DTC P062D FUEL INJECTOR DRIVER CIRCUIT

PERFORMANCE (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine does not start.

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 302 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-303

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

#1 (E158) No. 11 — (E158) No. 12:

#2 (E158) No. 23 — (E158) No. 24:

#3 (E158) No. 35 — (E158) No. 36:

#4 (E158) No. 47 — (E158) No. 48:

Is resistance 1.89 — 2.31 Ω at

20°C (68°F)?

Go to step 4. Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Disconnect the connector from fuel injector.

2) Measure the resistance of harness between

ECM connector and defective fuel injector con-

nector.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Repair or replace

the following items.

• Poor contact of

fuel injector con-

nector

• Defective fuel

injector <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

4 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of ECM

connector.

Go to step 5.

15WRX_STI_US_EN.book 303 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-304

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DW:DTC P062F INTERNAL CONTROL MODULE EEPROM ERROR

NOTE:

For the diagnostic procedure, refer to DTC P0606. <Ref. to EN(w/o STI)(diag)-291, DTC P0606 CONTROL

MODULE PROCESSOR, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

5 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Disconnect the connector from fuel injector.

2) Measure the resistance between ECM con-

nector and engine ground on defective fuel

injectors.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the faulty

fuel injector. <Ref.

to FU(w/o STI)-51,

Fuel Injector.>

Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

Step Check Yes No

15WRX_STI_US_EN.book 304 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-305

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DX:DTC P0685 ECM/PCM POWER RELAY CONTROL CIRCUIT/OPEN

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-161, DTC P0685 ECM/PCM POWER RELAY CON-

TROL CIRCUIT/OPEN, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B72

B550

923

B225

36 37

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B550

215

B220

B134A:

E159C:

A32

A23

A38

A24

A12

B220 B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10792

C25

C26

B22

A47

A35

C10

C17

C18

B72

7856

3412

ECM

SBF-7

SBF-6

232221 262524201918

587

10 11

B550

: WITHOUT PUSH BUTTON START

: WITH PUSH BUTTON START

BATTERY

MAIN

RELAY

FUSE HOLDER

M/B No. 13

F/B No. 12

(BROWN)

(GRAY)

IG RELAY 1

(PUSH BUTTON

START)

FUSE HOLDER

IGNITION

SWITCH

MAIN SBF

15WRX_STI_US_EN.book 305 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-306

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DY:DTC P0700 TRANSMISSION CONTROL SYSTEM (MIL REQUEST)

NOTE:

For the diagnostic procedure, refer to CVT section. <Ref. to CVT(diag)-2, Basic Diagnostic Procedure.>

Step Check Yes No

1 CHECK ECM CONNECTOR.

Check the connecting condition of ECM con-

nector.

Is the ECM connector correctly

connected?

Go to step 2. Connect the ECM

connector cor-

rectly.

2 CHECK HARNESS BETWEEN ECM AND

MAIN RELAY CONNECTOR.

1) Turn the ignition switch to OFF.

2) Remove the main relay.

3) Disconnect the connector from ECM.

4) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 38 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 3. Repair the short

circuit to ground in

harness between

ECM connector

and main relay

connector.

3 CHECK HARNESS BETWEEN ECM AND

MAIN RELAY CONNECTOR.

1) Install the main relay.

2) Turn the ignition switch to ON.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 12 (+) — Engine ground (–):

(B134) No. 24 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Short circuit to

power supply in

harness between

ECM connector

and main relay

connector

• Defective main

relay

Repair the poor

contact of ECM

connector.

15WRX_STI_US_EN.book 306 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-307

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

DZ:DTC P081A STARTER DISABLE CIRCUIT LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-163, DTC P081A STARTER DISABLE CIRCUIT LOW,

Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Failure of engine to start

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 307 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-308

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

CVT

B23

12345

6789

CVT

721

B12

B134

B14

B574C:

B572A:

B576B575

B106

B225

39 38

B225

B106

B550

923

B225

PRND

B12

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

19 20 21 22 23 24 25 26 27 28 29 30

789

10 11 12 13 14 15 16 17 18

123 456

B574C:

11 12

13 14

15 16

17 18

B572A:

B575

123

456789

10 11

12 13 14 15 16 17 18 19 20 21 22

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10791

B14

B23 B28

B550

822

232221 262524201918

587

10 11

B550

SBF-6

ECM

FUSE

HOLDER

(BROWN)

INHIBITOR

SWITCH

STARTER

CUT

RELAY

FUSE HOLDER

BATTERY

MAIN SBF

IG RELAY 1

(PUSH BUTTON

START)

F/B No. 26

STARTER RELAY

(PUSH BUTTON START)

STARTER

RELAY 1

CLUTCH

START

SWITCH

F/B No. 21

KEYLESS

ACCESS CM

STARTER MOTOR

15WRX_STI_US_EN.book 308 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-309

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN STARTER RE-

LAY (PUSH BUTTON START) CONNECTOR

AND STARTER CUT RELAY CONNECTOR.

1) Turn the ignition to OFF.

2) Remove the starter relay (push button start)

and starter cut relay.

3) Measure the resistance of harness between

starter relay (push button start) connector and

starter cut relay connector.

Connector & terminal

(B225) No. 28 — (B225) No. 42:

Is the resistance less than 1 Ω? Go to step 2. Repair the open

circuit in harness

between starter

relay (push button

start) connector

and starter cut

relay connector.

2 CHECK HARNESS BETWEEN ECM AND

STARTER CUT RELAY CONNECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance of harness between

ECM connector and starter cut relay connector.

Connector & terminal

(B134) No. 13 — (B225) No. 40:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of harness

between ECM con-

nector and starter

cut relay connec-

tor.

3 CHECK STARTER CUT RELAY.

1) Connect the battery to starter cut relay ter-

minals No. 40 and No. 42.

2) Measure the resistance between starter cut

relay terminals.

Terminals

No. 41 — No. 44:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of ECM

connector.

Replace the starter

cut relay. <Ref. to

SL-116, Starter

Cut Relay.>

15WRX_STI_US_EN.book 309 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-310

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EA:DTC P0851 PARK/NEUTRAL SWITCH INPUT CIRCUIT LOW (AT MODEL)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-164, DTC P0851 PARK/NEUTRAL SWITCH INPUT

CIRCUIT LOW (AT MODEL), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK SELECT CABLE. Is there any fault in select

cable?

Repair or adjust

the select cable.

<Ref. to CS-42,

Select Cable.>

Go to step 2.

2 CHECK INPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Place the select lever in other than “P” range

and “N” range.

3) Measure the voltage between ECM connec-

tor and chassis ground.

Connector & terminal

(B134) No. 33 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the poor

contact of ECM

connector.

Go to step 3.

ECM

T2B25

B22

5678

10 11 12

1413 15 16

B22

CVT

B25

T3B12

22 8

B550

B12

B14

EN-10834

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

B134

33 6

B14

PRND

232221 262524201918

587

10 11

B550

INHIBITOR SWITCH

STARTER MOTOR

(BROWN)

FUSE HOLDER

NEUTRAL POSITION

SWITCH

15WRX_STI_US_EN.book 310 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-311

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

3 CHECK HARNESS BETWEEN ECM AND

TRANSMISSION HARNESS CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

transmission harness connector (T3).

3) Measure the resistance between ECM con-

nector and chassis ground.

Connector & terminal

(B134) No. 33 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair the short

circuit to ground in

harness between

ECM connector

and transmission

harness connec-

tor.

4 CHECK TRANSMISSION HARNESS CON-

NECTOR.

1) Disconnect the connector from inhibitor

switch.

2) Measure the resistance between transmis-

sion harness connector and engine ground.

Connector & terminal

(T3) No. 12 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the inhibi-

tor switch. <Ref. to

CVT(TR690)-92,

Inhibitor Switch.>

Repair short cir-

cuit to ground in

harness between

transmission har-

ness connector

and inhibitor switch

connector.

Step Check Yes No

15WRX_STI_US_EN.book 311 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-312

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EB:DTC P0851 NEUTRAL SWITCH INPUT CIRCUIT LOW (MT MODEL)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-165, DTC P0851 NEUTRAL SWITCH INPUT CIRCUIT

LOW (MT MODEL), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK INPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Place the shift lever in a position other than

neutral.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 33 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the poor

contact of ECM

connector.

Go to step 2.

ECM

T2B25

B22

5678

10 11 12

1413 15 16

B22

CVT

B25

T3B12

22 8

B550

B12

B14

EN-10834

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

B134

33 6

B14

PRND

232221 262524201918

587

10 11

B550

INHIBITOR SWITCH

STARTER MOTOR

(BROWN)

FUSE HOLDER

NEUTRAL POSITION

SWITCH

15WRX_STI_US_EN.book 312 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-313

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK HARNESS BETWEEN ECM AND

NEUTRAL POSITION SWITCH CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

neutral position switch.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 33 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the neu-

tral position switch.

<Ref. to

6MT(TY75)-45,

Switches and Har-

ness.>

Repair the short

circuit to ground

harness between

ECM connector

and neutral posi-

tion switch connec-

tor.

Step Check Yes No

15WRX_STI_US_EN.book 313 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-314

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EC:DTC P0852 PARK/NEUTRAL SWITCH INPUT CIRCUIT HIGH (AT MODEL)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-166, DTC P0852 PARK/NEUTRAL SWITCH INPUT

CIRCUIT HIGH (AT MODEL), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK SELECT CABLE. Is there any fault in select

cable?

Repair or adjust

the select cable.

<Ref. to CS-42,

Select Cable.>

Go to step 2.

2 CHECK INPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM and

chassis ground with select lever at “P” range

and “N” range.

Connector & terminal

(B134) No. 33 (+) — Chassis ground (–):

Is the voltage less than 1 V? Repair the poor

contact of ECM

connector.

Go to step 3.

ECM

T2B25

B22

5678

10 11 12

1413 15 16

B22

CVT

B25

T3B12

22 8

B550

B12

B14

EN-10834

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

B134

33 6

B14

PRND

232221 262524201918

587

10 11

B550

INHIBITOR SWITCH

STARTER MOTOR

(BROWN)

FUSE HOLDER

NEUTRAL POSITION

SWITCH

15WRX_STI_US_EN.book 314 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-315

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

3 CHECK HARNESS BETWEEN ECM AND IN-

HIBITOR SWITCH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

inhibitor switch.

3) Measure the resistance of harness between

ECM connector and inhibitor switch connector.

Connector & terminal

(B134) No. 33 — (T7) No. 6:

Is the resistance less than 1 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Blown out of fuse

• Open circuit in

harness between

ECM connector

and inhibitor switch

connector

• Poor contact of

coupling connector

4 CHECK INHIBITOR SWITCH GROUND LINE.

Measure the resistance of harness between

inhibitor switch connector and engine ground.

Connector & terminal

(T7) No. 9 — Engine ground:

Is the resistance less than 5 Ω? Replace the inhibi-

tor switch. <Ref. to

CVT(TR690)-92,

Inhibitor Switch.>

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

inhibitor switch

connector and

starter motor

ground line

• Poor contact of

coupling connector

• Poor contact of

starter motor con-

nector

• Poor contact of

starter motor

ground

• Starter motor

Step Check Yes No

15WRX_STI_US_EN.book 315 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-316

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

ED:DTC P0852 NEUTRAL SWITCH INPUT CIRCUIT HIGH (MT MODEL)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-167, DTC P0852 NEUTRAL SWITCH INPUT CIRCUIT

HIGH (MT MODEL), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK INPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Place the shift lever in neutral.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 33 (+) — Engine ground (–):

Is the voltage less than 1 V? Repair the poor

contact of ECM

connector.

Go to step 2.

ECM

T2B25

B22

5678

10 11 12

1413 15 16

B22

CVT

B25

T3B12

22 8

B550

B12

B14

EN-10834

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

2345

B134

33 6

B14

PRND

232221 262524201918

587

10 11

B550

INHIBITOR SWITCH

STARTER MOTOR

(BROWN)

FUSE HOLDER

NEUTRAL POSITION

SWITCH

15WRX_STI_US_EN.book 316 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-317

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK HARNESS BETWEEN ECM AND

NEUTRAL POSITION SWITCH CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

neutral position switch.

3) Measure the resistance of harness between

ECM connector and neutral position switch con-

nector.

Connector & terminal

(B134) No. 33 — (B25) No. 2:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit in harness

between ECM con-

nector and trans-

mission harness

connector.

3 CHECK HARNESS BETWEEN NEUTRAL

POSITION SWITCH CONNECTOR AND

CHASSIS GROUND.

Measure the resistance of harness between

neutral position switch connector and chassis

ground.

Connector & terminal

(B25) No. 1 — Chassis ground:

Is the resistance less than 5 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

neutral position

switch connector

and chassis

ground

• Poor contact of

coupling connector

4 CHECK NEUTRAL POSITION SWITCH.

1) Place the shift lever in neutral.

2) Measure the resistance between neutral

position switch connector terminals.

Connector & terminal

(T2) No. 1 — (T2) No. 2:

Is the resistance less than 1 Ω? Repair the poor

contact of neutral

position switch

connector.

Replace the neu-

tral position switch.

<Ref. to

6MT(TY75)-45,

Switches and Har-

ness.>

Step Check Yes No

15WRX_STI_US_EN.book 317 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-318

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EE:DTC P1134 A/F SENSOR MICRO-COMPUTER PROBLEM

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-168, DTC P1134 A/F SENSOR MICRO-COMPUTER

PROBLEM, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

15WRX_STI_US_EN.book 318 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-319

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EF:DTC P113A O2 SENSOR CIRCUIT (OPEN) (BANK1 SENSOR2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-169, DTC P113A O2 SENSOR CIRCUIT (OPEN)

(BANK1 SENSOR2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 319 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-320

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

keep the engine speed at 3,000 rpm. (2 minutes

maximum)

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.490 V or more?

Go to step 6. Go to step 3.

3 CHECK REAR OXYGEN SENSOR CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 5. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

5 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 16 — Engine ground

(E158) No. 42 — Engine ground

Is the resistance 1 Ω or more? Go to step 6. Repair the short

circuit to ground in

harness between

ECM connector

and rear oxygen

sensor connector.

6 CHECK EXHAUST SYSTEM.

Check exhaust system parts.

NOTE:

Check the following items.

• Looseness and improper fitting of exhaust

system parts

• Damage (crack, hole etc.) of parts

• Loose part and improper installation between

front oxygen (A/F) sensor and rear oxygen sen-

sor

Is there any fault in exhaust

system?

Repair or replace

faulty parts.

Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

15WRX_STI_US_EN.book 320 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-321

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EG:DTC P1160 RETURN SPRING FAILURE

NOTE:

For the diagnostic procedure, refer to DTC P2101. <Ref. to EN(w/o STI)(diag)-423, DTC P2101 THROTTLE

ACTUATOR CONTROL MOTOR CIRCUIT RANGE/PERFORMANCE, Diagnostic Procedure with Diagnos-

tic Trouble Code (DTC).>

15WRX_STI_US_EN.book 321 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-322

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EH:DTC P1261 DI INJECTOR CIRCUIT / OPEN - (CYLINDER 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-171, DTC P1261 DI INJECTOR CIRCUIT / OPEN -

(CYLINDER 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 322 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-323

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EI: DTC P1262 DI INJECTOR CIRCUIT / OPEN - (CYLINDER 2)

NOTE:

For the diagnostic procedure, refer to DTC P1261. <Ref. to EN(w/o STI)(diag)-322, DTC P1261 DI INJEC-

TOR CIRCUIT / OPEN - (CYLINDER 1), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

EJ:DTC P1263 DI INJECTOR CIRCUIT / OPEN - (CYLINDER 3)

NOTE:

For the diagnostic procedure, refer to DTC P1261. <Ref. to EN(w/o STI)(diag)-322, DTC P1261 DI INJEC-

TOR CIRCUIT / OPEN - (CYLINDER 1), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

EK:DTC P1264 DI INJECTOR CIRCUIT / OPEN - (CYLINDER 4)

NOTE:

For the diagnostic procedure, refer to DTC P1261. <Ref. to EN(w/o STI)(diag)-322, DTC P1261 DI INJEC-

TOR CIRCUIT / OPEN - (CYLINDER 1), Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM ter-

minals on faulty fuel injectors.

Connector & terminal

#1 (E158) No. 11 — (E158) No. 12:

#2 (E158) No. 23 — (E158) No. 24:

#3 (E158) No. 35 — (E158) No. 36:

#4 (E158) No. 47 — (E158) No. 48:

Is resistance 1.89 — 2.31 Ω at

20°C (68°F)?

Go to step 2. Go to step 3.

2 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance between ECM and

engine ground on faulty injectors.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of ECM

connector.

Go to step 3.

3 CHECK FUEL INJECTOR.

Check the fuel injector on faulty cylinder. <Ref.

to FU(w/o STI)-70, INSPECTION, Fuel Injec-

tor.>

Are fuel injectors OK? Repair the open or

ground short circuit

in harness

between ECM con-

nector and fuel

injector connector.

Replace the faulty

fuel injector. <Ref.

to FU(w/o STI)-51,

Fuel Injector.>

15WRX_STI_US_EN.book 323 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-324

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EL:DTC P1449 EVAPORATIVE EMISSION CONT. SYS. AIR FILTER CLOG

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-173, DTC P1449 EVAPORATIVE EMISSION CONT.

SYS. AIR FILTER CLOG, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK DRAIN TUBE A AND DRAIN PIPE

BETWEEN LEAK CHECK VALVE ASSEM-

BLY AND DRAIN FILTER.

Is the drain tube A or the drain

pipe between leak check valve

assembly and drain filter

clogged?

Replace the drain

tube A or the drain

pipe between leak

check valve

assembly and

drain filter. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.> <Ref.

to EC(w/o STI)-50,

Drain Filter.>

Go to step 3.

3 CHECK DRAIN FILTER. Is the drain filter clogged? Replace the drain

filter. <Ref. to

EC(w/o STI)-50,

Drain Filter.>

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

15WRX_STI_US_EN.book 324 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-325

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EM:DTC P1451 EVAPORATIVE EMISSION CONT. SYS.

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-174, DTC P1451 EVAPORATIVE EMISSION CONT.

SYS., Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK DRAIN TUBE BETWEEN CANISTER

AND LEAK CHECK VALVE ASSEMBLY.

Is the drain tube between canis-

ter and leak check valve

assembly clogged?

Replace the drain

tube between the

canister and leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

Go to step 2.

2 CHECK HOSES BETWEEN CANISTER AND

FUEL TANK.

Are the hoses between the can-

ister and fuel tank clogged?

Replace the hoses

between the canis-

ter and fuel tank.

<Ref. to EC(w/o

STI)-8, Canister.>

<Ref. to FU(w/o

STI)-152, Fuel

Tan k. >

Replace the canis-

ter. <Ref. to EC(w/

o STI)-8, Canis-

ter.>

After the operation

is complete, go to

the next step. Go to

step 3.

3 CHECK EVAPORATIVE EMISSION CON-

TROL SYSTEM.

Perform drive cycle I. <Ref. to EN(w/o

STI)(diag)-56, DRIVE CYCLE I, PROCEDURE,

Drive Cycle.>

Is DTC P1451 displayed on the

display?

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

End.

15WRX_STI_US_EN.book 325 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-326

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EN:DTC P1458 CPC2 SOLENOID VALVE (CIRCUIT LOW)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-175, DTC P1458 CPC2 SOLENOID VALVE (CIRCUIT

LOW), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK OUTPUT SIGNAL OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 12 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

17 18

25 26

19 20

27 28

E159

E52

B22

EN-10809

B550

215

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E159

E52

212

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

PURGE CONTROL

SOLENOID VALVE 1

PURGE CONTROL

SOLENOID VALVE 2

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 326 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-327

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

3 CHECK POWER SUPPLY TO PURGE CON-

TROL SOLENOID VALVE 2.

Measure the voltage between purge control

solenoid valve 2 connector and engine ground.

Connector & terminal

(E52) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 2

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

purge control solenoid valve 2.

3) Measure the resistance between the purge

control solenoid valve 2 connector and engine

ground.

Connector & terminal

(E52) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the ground

short circuit of har-

ness between

ECM connector

and purge control

solenoid valve 2

connector.

5 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 2

CONNECTOR.

Measure the resistance of harness between

ECM connector and purge control solenoid

valve 2 connector.

Connector & terminal

(E159) No. 12 — (E52) No. 2:

Is the resistance less than 1 Ω? Go to step 6. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and purge control

solenoid valve 2

connector

• Poor contact of

coupling connector

6 CHECK PURGE CONTROL SOLENOID

VALVE 2.

1) Remove the purge control solenoid valve 2.

2) Measure the resistance between purge con-

trol solenoid valve 2 terminals.

Terminals

No. 1 — No. 2:

Is the resistance 10 — 100 Ω? Repair the poor

contact of the

purge control sole-

noid valve 2 con-

nector.

Replace the purge

control solenoid

valve 2. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

Step Check Yes No

15WRX_STI_US_EN.book 327 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-328

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EO:DTC P1459 CPC2 SOLENOID VALVE (CIRCUIT HIGH)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-176, DTC P1459 CPC2 SOLENOID VALVE (CIRCUIT

HIGH), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 2

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

purge control solenoid valve 2.

3) Turn the ignition switch to ON.

4) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 12 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

harness between

ECM connector

and purge control

solenoid valve 2

connector.

Go to step 2.

17 18

25 26

19 20

27 28

E159

E52

B22

EN-10809

B550

215

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E159

E52

212

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

PURGE CONTROL

SOLENOID VALVE 1

PURGE CONTROL

SOLENOID VALVE 2

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 328 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-329

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EP:DTC P1492 EGR SOLENOID VALVE SIGNAL #1 CIRCUIT MALFUNCTION

(LOW INPUT)

NOTE:

For the diagnostic procedure, refer to DTC P1498. <Ref. to EN(w/o STI)(diag)-330, DTC P1498 EGR SOLE-

NOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION (LOW INPUT), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

EQ:DTC P1493 EGR SOLENOID VALVE SIGNAL #1 CIRCUIT MALFUNCTION

(HIGH INPUT)

NOTE:

For the diagnostic procedure, refer to DTC P1499. <Ref. to EN(w/o STI)(diag)-332, DTC P1499 EGR SOLE-

NOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION (HIGH INPUT), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

ER:DTC P1494 EGR SOLENOID VALVE SIGNAL #2 CIRCUIT MALFUNCTION

(LOW INPUT)

NOTE:

For the diagnostic procedure, refer to DTC P1498. <Ref. to EN(w/o STI)(diag)-330, DTC P1498 EGR SOLE-

NOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION (LOW INPUT), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

ES:DTC P1495 EGR SOLENOID VALVE SIGNAL #2 CIRCUIT MALFUNCTION

(HIGH INPUT)

NOTE:

For the diagnostic procedure, refer to DTC P1499. <Ref. to EN(w/o STI)(diag)-332, DTC P1499 EGR SOLE-

NOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION (HIGH INPUT), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

ET:DTC P1496 EGR SOLENOID VALVE SIGNAL #3 CIRCUIT MALFUNCTION

(LOW INPUT)

NOTE:

For the diagnostic procedure, refer to DTC P1498. <Ref. to EN(w/o STI)(diag)-330, DTC P1498 EGR SOLE-

NOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION (LOW INPUT), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

EU:DTC P1497 EGR SOLENOID VALVE SIGNAL #3 CIRCUIT MALFUNCTION

(HIGH INPUT)

NOTE:

For the diagnostic procedure, refer to DTC P1499. <Ref. to EN(w/o STI)(diag)-332, DTC P1499 EGR SOLE-

NOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION (HIGH INPUT), Diagnostic Procedure with Diagnostic

Trouble Code (DTC).>

2 CHECK PURGE CONTROL SOLENOID

VALVE 2.

1) Turn the ignition switch to OFF.

2) Measure the resistance between purge con-

trol solenoid valve 2 terminals.

Terminals

No. 1 — No. 2:

Is the resistance less than 1 Ω? Replace the purge

control solenoid

valve 2. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

Repair the poor

contact of ECM

connector.

Step Check Yes No

15WRX_STI_US_EN.book 329 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-330

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EV:DTC P1498 EGR SOLENOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION

(LOW INPUT)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-178, DTC P1498 EGR SOLENOID VALVE SIGNAL #4

CIRCUIT MALFUNCTION (LOW INPUT), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Engine breathing

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

EN-10811

E18

E159

B550

215

B220

645

E18

17 18

25 26

19 20

27 28

E159

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

(GRAY)

MAIN RELAY

BATTERY

FUSE HOLDER

EGR

CONTROL VALVE

15WRX_STI_US_EN.book 330 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-331

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK POWER SUPPLY TO EGR CON-

TROL VALVE.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the EGR

control valve.

3) Turn the ignition switch to ON.

4) Measure the voltage between EGR control

valve connector and engine ground.

Connector & terminal

(E18) No. 2 (+) — Engine ground (–):

(E18) No. 5 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

EGR control valve

and main relay

connector

• Poor contact of

coupling connector

2 CHECK HARNESS BETWEEN ECM AND

EGR CONTROL VALVE CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and EGR control valve connector.

Connector & terminal

DTC P1492; (E159) No. 5 — (E18) No. 3:

DTC P1494; (E159) No. 21 — (E18) No. 1:

DTC P1496; (E159) No. 13 — (E18) No. 4:

DTC P1498; (E159) No. 29 — (E18) No. 6:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of the har-

ness between the

ECM connector

and EGR control

valve connector.

3 CHECK HARNESS BETWEEN ECM AND

EGR CONTROL VALVE CONNECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

DTC P1492; (E159) No. 5 — Engine

ground:

DTC P1494; (E159) No. 21 — Engine

ground:

DTC P1496; (E159) No. 13 — Engine

ground:

DTC P1498; (E159) No. 29 — Engine

ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair ground

short circuit of har-

ness between

ECM connector

and EGR control

valve connector.

4 CHECK FOR POOR CONTACT.

Check for poor contact between ECM connec-

tor and EGR control valve connector.

Is there poor contact in ECM or

EGR control valve connector?

Repair the poor

contact of ECM or

EGR control valve

connector.

Replace EGR con-

trol valve. <Ref. to

EC(w/o STI)-35,

EGR Control

Valve.>

15WRX_STI_US_EN.book 331 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-332

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EW:DTC P1499 EGR SOLENOID VALVE SIGNAL #4 CIRCUIT MALFUNCTION

(HIGH INPUT)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-179, DTC P1499 EGR SOLENOID VALVE SIGNAL #4

CIRCUIT MALFUNCTION (HIGH INPUT), Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Engine breathing

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

EN-10811

E18

E159

B550

215

B220

645

E18

17 18

25 26

19 20

27 28

E159

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

(GRAY)

MAIN RELAY

BATTERY

FUSE HOLDER

EGR

CONTROL VALVE

15WRX_STI_US_EN.book 332 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-333

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

EGR CONTROL VALVE CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

EGR control valve.

3) Turn the ignition switch to ON.

4) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

DTC P1493; (E159) No. 5 (+) — Engine

ground (–):

DTC P1495; (E159) No. 21 (+) — Engine

ground (–):

DTC P1497; (E159) No. 13 (+) — Engine

ground (–):

DTC P1499; (E159) No. 29 (+) — Engine

ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power

supply in the har-

ness between the

ECM connector

and EGR control

valve connector.

Go to step 2.

2 CHECK EGR CONTROL VALVE.

Measure the resistance between EGR control

valve terminals.

Terminals

DTC P1493; No. 2 — No. 3:

DTC P1495; No. 2 — No. 1:

DTC P1497; No. 5 — No. 4:

DTC P1499; No. 5 — No. 6:

Is the resistance 20 Ω or more? Repair the poor

contact of ECM

connector.

Replace EGR con-

trol valve. <Ref. to

EC(w/o STI)-35,

EGR Control

Valve.>

15WRX_STI_US_EN.book 333 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-334

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EX:DTC P1603 ENGINE STALL HISTORY

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-180, DTC P1603 ENGINE STALL HISTORY, Diagnostic

Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode. <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>

NOTE:

This DTC may be detected even if fault does not occur in the vehicle. If the customer does not ask for in-

spection, perform the clear memory mode without inspection and return the vehicle to the user.

15WRX_STI_US_EN.book 334 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-335

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E3 B22

B122

EN-10799

123

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B122

J/C

B550

215

B220

B134A:

E158B:

A19

A16

A28

SBF-7

ECM

232221 262524201918

587

10 11

B550

: TERMINAL No. OPTIONAL

ARRANGEMENT

MAIN RELAY

BATTERY

FUSE HOLDER

MASS AIR FLOW &

INTAKE AIR TEMPERATURE SENSOR

(BROWN)

(BLACK)

15WRX_STI_US_EN.book 335 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-336

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 336 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-337

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

E158B:

E159C:

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

C27

B38

EN-10322

ECM

ENGINE COOLANT

TEMPERATURE

SENSOR

(GRAY)

(BLACK)

17 18

25 26

19 20

27 28

E159

E52

B22

EN-10809

B550

215

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E159

E52

212

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

PURGE CONTROL

SOLENOID VALVE 1

PURGE CONTROL

SOLENOID VALVE 2

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 337 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-338

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E3B22

B550

215

B220

E38E37

E38

EN-10796

E159

215

E37

SBF-7

ECM

232221 262524201918

587

10 11

B550

INTAKE

OIL CONTROL

SOLENOID LH

INTAKE

OIL CONTROL

SOLENOID RH

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

ECM

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E3B22

B550

215

B220

E66E63

E63

223

EN-10795

E159

231

E66

SBF-7

232221 262524201918

587

10 11

B550

EXHAUST

OIL CONTROL

SOLENOID LH

EXHAUST

OIL CONTROL

SOLENOID RH

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 338 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-339

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK DTC. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Go to step 2.

2 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the value

in «Fuel Level».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Fuel Level»

16.4% or more?

Go to step 3. Fuel may be run

out. If the fault

occurs after refuel-

ing, continue the

diagnosis. Go to

step 3.

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 339 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-340

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

3 CHECK FREEZE FRAME DATA.

Read the value of «Control module voltage»

using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Control module

voltage» 11 V or more?

Go to step 4. Check the battery

and generator.

<Ref. to SC(w/o

STI)-51, INSPEC-

TION, Battery.>

<Ref. to SC(w/o

STI)-45, INSPEC-

TION, Generator.>

4 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Did you ask the customer about

the driving condition and

engine speed status when the

fault occurred?

• The engine

speed dropped

slowly and then the

engine stalled dur-

ing idling or decel-

eration: Go to step

• The engine

speed dropped

rapidly and then

the engine stalled

during idling or

deceleration: Go to

step 82.

• The engine

stalled during

standing start,

acceleration, or

constant speed

driving: Go to step

89.

Ask the customer

about the driving

condition and

engine speed sta-

tus when fault

occurred.

5 CHECK FREEZE FRAME DATA.

1) Read the values of «Short term fuel trim

B1» and «Long term fuel trim B1», using the

Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

2) Obtain the sum values of «Short term fuel

trim B1» and «Long term fuel trim B1» in each

freeze frame data.

Is the sum value of «Short term

fuel trim B1» and «Long term

fuel trim B1» within ±15% in

each freeze frame data?

Go to step 56. • More than 15%

in each freeze

frame data: Go to

step 6.

• Less than –15%

in any one of

freeze frame data:

Go to step 40.

6 CHECK AIR INTAKE SYSTEM.

Check the installing condition of the air intake

system.

Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

<Ref. to IN(w/o

STI)-2, General

Description.>

Go to step 7.

7 CHECK PURGE CONTROL SOLENOID

VALVE.

Check purge control solenoid valve 1 and purge

control solenoid valve 2. <Ref. to EC(w/o STI)-

29, INSPECTION, Purge Control Solenoid

Valve.>

Are the purge control solenoid

valve 1 and the purge control

solenoid valve 2 normal?

Go to step 8. Replace the faulty

purge control sole-

noid valve. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

Step Check Yes No

15WRX_STI_US_EN.book 340 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-341

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

8 CHECK FREEZE FRAME DATA.

Read the value of «Stop Light Switch» using

Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Does the value of «Stop Light

Switch» indicate OFF in all

freeze frame data?

Go to step 11. Go to step 9.

9 CHECK CURRENT DATA.

1) Start the engine and warm up completely.

2) Read the value of «Short term fuel trim B1»

both when the brake pedal is released and

depressed using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Does the value of «Short term

fuel trim B1» with the brake

pedal depressed increase by

10% or more compared to

when the pedal is released?

Replace the brake

booster. <Ref. to

BR-55, Brake

Booster.>

Go to step 10.

10 CHECK CURRENT DATA.

1) Start the engine and warm up completely.

2) While reproducing the faulty condition of the

vehicle, read the values of «Short term fuel trim

B1» and «Long term fuel trim B1» using the

Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

3) Obtain the sum values of «Short term fuel

trim B1» and «Long term fuel trim B1».

Is the sum value of «Short term

fuel trim B1» and «Long term

fuel trim B1» within ±15%?

Go to step 11. Replace the brake

booster. <Ref. to

BR-55, Brake

Booster.>

11 CHECK IGNITION SYSTEM.

Check the ignition system. <Ref. to EN(w/o

STI)(diag)-80, IGNITION CONTROL SYSTEM,

Diagnostics for Engine Starting Failure.>

Is the ignition system normal? Go to step 12. Repair the ignition

system. <Ref. to

IG(w/o STI)-2,

General Descrip-

tion.>

12 CHECK FREEZE FRAME DATA.

Read the value of «A/F Sensor #1» using the

Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «A/F Sensor #1»

1.00 or more?

Go to step 17. Go to step 13.

13 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

Check the mass air flow and intake air tempera-

ture sensor. <Ref. to FU(w/o STI)-118,

INSPECTION, Mass Air Flow and Intake Air

Temperature Sensor.>

Is the mass air flow and intake

air temperature sensor normal?

Go to step 14. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 341 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-342

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

14 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the mass air flow and intake air temperature

sensor.

3) Measure the resistance of harness between

ECM connector and the mass air flow and

intake air temperature sensor connector.

Connector & terminal

(B134) No. 16 — (B3) No. 3:

(B134) No. 28 — (B3) No. 2:

Is the resistance less than 1 Ω? Go to step 15. Repair the open

circuit of harness

between ECM con-

nector and the

mass air flow and

intake air tempera-

ture sensor con-

nector.

15 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(B134) No. 16 — Engine ground:

(B134) No. 28 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 16. Repair the ground

short circuit of har-

ness between

ECM connector

and the mass air

flow and intake air

temperature sen-

sor connector.

16 CHECK CURRENT DATA.

1) Start the engine and warm up completely.

2) Using the Subaru Select Monitor, read the

value of «Calculated load value», then compare

it with that of «Calculated load value» listed in

“Engine Current Data Display”. <Ref. to EN(w/o

STI)(diag)-37, DISPLAY CURRENT ENGINE

DATA, OPERATION, Subaru Select Monitor.>

NOTE:

• The value of «Calculated load value» change

depending on how the engine internal parts set-

tle in. If the value is out of standard, judge it

again by comparing the vehicle with another

one with the same specifications and similar

conditions such as travel distance.

• For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Does the value of «Calculated

load value» falls between 90 —

110% of the value described in

the list?

Go to step 21. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

17 CHECK FRONT OXYGEN (A/F) SENSOR DA-

TA.

1) Start the engine and warm up completely.

2) Raise the engine speed up to 2,500 rpm and

maintain it for approx. three minutes.

3) Release the accelerator pedal and idle the

engine.

4) Using «Injection Quantity Control» in «Sys-

tem Operation Check Mode», read the value of

«A/F Sensor #1» at the increase rate of both

12% and –12%.

NOTE:

• Perform the operation immediately after the

engine comes into idling condition, otherwise

the front oxygen (A/F) sensor will be cooled.

• For detailed procedures, refer to “System Op-

eration Check Mode”. <Ref. to EN(w/o STI)(di-

ag)-62, System Operation Check Mode.>

Does the value of «A/F Sensor

#1» change to less than 0.88

at the increase rate of 12%,

and to 1.12 or more at the rate

of –12%?

Go to step 21. Go to step 18.

Step Check Yes No

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EN(w/o STI)(diag)-343

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

18 CHECK POWER SUPPLY TO FRONT OXY-

GEN (A/F) SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from front oxy-

gen (A/F) sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between front oxygen

(A/F) sensor connector and engine ground.

Connector & terminal

(E24) No. 3 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 19. Repair the power

supply line.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

A/F, oxygen sen-

sor relay and front

oxygen (A/F) sen-

sor connector

• Poor contact of

A/F, oxygen sen-

sor relay connector

• Poor contact of

coupling connector

• Malfunction of A/

F, oxygen sensor

relay

19 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

(E159) No. 9 — (E24) No. 2:

Is the resistance less than 1 Ω? Go to step 20. Repair the open

circuit of harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

20 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 15 — Engine ground:

(E158) No. 27 — Engine ground:

(E158) No. 39 — Engine ground:

(E159) No. 9 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 21. Repair the short

circuit to ground in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector.

21 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Coolant Temp.» and «Ambient Temper-

ature».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Coolant Temp.»

120°C (248°F) or more? Or, is

the value of «Coolant Temp.»

lower than «Ambient Tempera-

ture» by 15°C (27°F) or more?

Go to step 22. Go to step 25.

22 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

Check the engine coolant temperature sensor.

<Ref. to FU(w/o STI)-94, INSPECTION, Engine

Coolant Temperature Sensor.>

Is the engine coolant tempera-

ture sensor normal?

Go to step 23. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

Step Check Yes No

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EN(w/o STI)(diag)-344

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

23 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

engine coolant temperature sensor.

3) Measure the resistance of harness between

ECM connector and engine coolant tempera-

ture sensor connector.

Connector & terminal

(E159) No. 27 — (E8) No. 1:

(E158) No. 38 — (E8) No. 2:

Is the resistance less than 1 Ω? Go to step 24. Repair the open

circuit of the har-

ness between the

ECM connector

and engine coolant

temperature sen-

sor connector.

24 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 38 — Engine ground:

(E159) No. 27 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 25. Repair the short

circuit to ground in

harness between

ECM connector

and engine coolant

temperature sen-

sor connector.

25 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the value

in «Evap Purge Flow».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Evap Purge

Flow» 0% in all freeze frame

data?

Go to step 35. Go to step 26.

26 CHECK PURGE CONTROL SOLENOID

VALVE 1.

1) Select «CPC Solenoid Valve» from “Actua-

tor ON/OFF Operation” in “System Operation

Check Mode”.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

2) Check if the ventilation changes according

to ON/OFF switching operation.

Does the ventilation of purge

control solenoid valve 1 change

correctly?

Go to step 30. Go to step 27.

27 CHECK POWER SUPPLY TO PURGE CON-

TROL SOLENOID VALVE 1 CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from purge con-

trol solenoid valve 1.

3) Turn the ignition switch to ON.

4) Measure the voltage between purge control

solenoid valve 1 connector and engine ground.

Connector & terminal

(E4) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 28. Repair the power

supply circuit.

28 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 1

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and purge control solenoid

valve 1 connector.

Connector & terminal

(E159) No. 4 — (E4) No. 2:

Is the resistance less than 1 Ω? Go to step

29. Repair the open

circuit in harness

between ECM con-

nector and purge

control solenoid

valve 1 connector.

Step Check Yes No

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EN(w/o STI)(diag)-345

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

29 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 1

CONNECTOR.

Measure the resistance between the purge con-

trol solenoid valve 1 connector and engine

ground.

Connector & terminal

(E4) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 30. Repair the ground

short circuit of har-

ness between

ECM connector

and purge control

solenoid valve 1

connector.

30 CHECK PURGE CONTROL SOLENOID

VALVE 2.

1) Connect all connectors.

2) Select «CPC Solenoid 2» from “Actuator

ON/OFF Operation” in “System Operation

Check Mode”.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

3) Check if the ventilation changes according

to ON/OFF switching operation.

Does the ventilation of purge

control solenoid valve 2 change

correctly?

Go to step 35. Go to step 31.

31 CHECK POWER SUPPLY TO PURGE CON-

TROL SOLENOID VALVE 2 CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from purge con-

trol solenoid valve 2.

3) Turn the ignition switch to ON.

4) Measure the voltage between purge control

solenoid valve 2 connector and engine ground.

Connector & terminal

(E52) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 32. Repair the power

supply circuit.

32 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 2

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and purge control solenoid

valve 2 connector.

Connector & terminal

(E159) No. 12 — (E52) No. 2:

Is the resistance less than 1 Ω? Go to step 33. Repair the open

circuit in harness

between ECM con-

nector and purge

control solenoid

valve 2 connector.

33 CHECK HARNESS BETWEEN ECM AND

PURGE CONTROL SOLENOID VALVE 2

CONNECTOR.

Measure the resistance between the purge con-

trol solenoid valve 2 connector and engine

ground.

Connector & terminal

(E52) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 34. Repair the ground

short circuit of har-

ness between

ECM connector

and purge control

solenoid valve 2

connector.

34 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

Step Check Yes No

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EN(w/o STI)(diag)-346

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

35 CHECK OF FUEL PUMP.

1) Select «Fuel Pump» from “Actuator ON/

OFF Operation” in “System Operation Check

Mode”.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

2) Check if operating sound occurs in the fuel

pump according to ON/OFF switching opera-

tion.

Does the fuel pump emit oper-

ating sound?

Go to step 37. Go to step 36.

36 CHECK OF FUEL PUMP.

Check fuel pump. <Ref. to FU(w/o STI)-172,

INSPECTION, Fuel Pump.>

Is the fuel pump normal? Check fuel pump

system. <Ref. to

EN(w/o STI)(diag)-

209, DTC P0230

FUEL PUMP PRI-

MARY CIRCUIT,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).>

Replace the fuel

pump. <Ref. to

FU(w/o STI)-168,

Fuel Pump.>

37 CHECK FUEL TANK.

Check if any foreign matters such as iron pow-

der exist in the fuel tank.

Is there any foreign matter in

the fuel tank?

Remove foreign

matter from the

fuel tank.

Go to step 38.

38 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 340 —

400 kPa (3.5 — 4.1 kgf/cm

, 49

— 58 psi)?

Go to step 39. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

39 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Fuel Rail Pressure A» and «Com-

manded Fuel Rail Pressure A».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value in «Fuel Rail Pres-

sure A» synchronized with the

one in «Commanded Fuel Rail

Pressure A» in all freeze frame

data?

Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Check the high-

pressure fuel

pump. <Ref. to

FU(w/o STI)-82,

INSPECTION,

High Pressure

Fuel Pump.>

40 CHECK IGNITION SYSTEM.

Check the ignition system. <Ref. to EN(w/o

STI)(diag)-80, IGNITION CONTROL SYSTEM,

Diagnostics for Engine Starting Failure.>

Is the ignition system normal? Go to step 41. Repair the ignition

system. <Ref. to

IG(w/o STI)-2,

General Descrip-

tion.>

Step Check Yes No

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EN(w/o STI)(diag)-347

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

41 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the value

of «Calculated load value», then compare it with

that of «Calculated load value» listed in “Engine

Current Data Display”. <Ref. to EN(w/o

STI)(diag)-37, DISPLAY CURRENT ENGINE

DATA, OPERATION, Subaru Select Monitor.>

NOTE:

• The value of «Calculated load value» change

depending on how the engine internal parts set-

tle in. If the value is out of standard, judge it

again by comparing the vehicle with another

one with the same specifications and similar

conditions such as travel distance.

• For detailed operation procedures, refer to

“Engine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Calculated load

value» 110% or more of the

value described in the list?

Go to step 43. Go to step 42.

42 CHECK FREEZE FRAME DATA.

Read the value of «A/F Sensor #1» using the

Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «A/F Sensor #1»

less than 1.00?

Go to step 47. Go to step 52.

43 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

Check the mass air flow and intake air tempera-

ture sensor. <Ref. to FU(w/o STI)-118,

INSPECTION, Mass Air Flow and Intake Air

Temperature Sensor.>

Is the mass air flow and intake

air temperature sensor normal?

Go to step 44. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

44 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the mass air flow and intake air temperature

sensor.

3) Measure the resistance of harness between

ECM connector and the mass air flow and

intake air temperature sensor connector.

Connector & terminal

(B134) No. 16 — (B3) No. 3:

(B134) No. 28 — (B3) No. 2:

Is the resistance less than 1 Ω? Go to step 45. Repair the open

circuit of harness

between ECM con-

nector and the

mass air flow and

intake air tempera-

ture sensor con-

nector.

45 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(B134) No. 16 — Engine ground:

(B134) No. 28 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 46. Repair the ground

short circuit of har-

ness between

ECM connector

and the mass air

flow and intake air

temperature sen-

sor connector.

Step Check Yes No

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EN(w/o STI)(diag)-348

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

46 CHECK CURRENT DATA.

1) Start the engine and warm up completely.

2) Using the Subaru Select Monitor, read the

value of «Calculated load value», then compare

it with that of «Calculated load value» listed in

“Engine Current Data Display”. <Ref. to EN(w/o

STI)(diag)-37, DISPLAY CURRENT ENGINE

DATA, OPERATION, Subaru Select Monitor.>

NOTE:

• The value of «Calculated load value» change

depending on how the engine internal parts set-

tle in. If the value is out of standard, judge it

again by comparing the vehicle with another

one with the same specifications and similar

conditions such as travel distance.

• For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Does the value of «Calculated

load value» falls between 90 —

110% of the value described in

the list?

Go to step 47. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

47 CHECK CURRENT DATA.

1) Start the engine and warm up completely.

2) Raise the engine speed up to 2,500 rpm and

maintain it for approx. three minutes.

3) Release the accelerator pedal and idle the

engine.

4) Using «Injection Quantity Control» in «Sys-

tem Operation Check Mode», read the value of

«A/F Sensor #1» at the increase rate of both

12% and –12%.

NOTE:

• Perform the operation immediately after the

engine comes into idling condition, otherwise

the front oxygen (A/F) sensor will be cooled.

• For detailed procedures, refer to “System Op-

eration Check Mode”. <Ref. to EN(w/o STI)(di-

ag)-62, System Operation Check Mode.>

Does the value of «A/F Sensor

#1» change to less than 0.88

at the increase rate of 12%,

and to 1.12 or more at the rate

of –12%?

Go to step 52. Go to step 48.

48 CHECK FREEZE FRAME DATA.

Read the value of «A/F Sensor #1 Resistance»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «A/F Sensor #1

Resistance» 500 Ω or more?

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

Go to step 49.

Step Check Yes No

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EN(w/o STI)(diag)-349

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

49 CHECK POWER SUPPLY TO FRONT OXY-

GEN (A/F) SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from front oxy-

gen (A/F) sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between front oxygen

(A/F) sensor connector and engine ground.

Connector & terminal

(E24) No. 3 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 50. Repair the power

supply line.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

A/F, oxygen sen-

sor relay and front

oxygen (A/F) sen-

sor connector

• Poor contact of

A/F, oxygen sen-

sor relay connector

• Poor contact of

coupling connector

• Malfunction of A/

F, oxygen sensor

relay

50 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

(E159) No. 9 — (E24) No. 2:

Is the resistance less than 1 Ω? Go to step 51. Repair the open

circuit of harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

51 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 15 — Engine ground:

(E158) No. 27 — Engine ground:

(E158) No. 39 — Engine ground:

(E159) No. 9 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 52. Repair the short

circuit to ground in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector.

52 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Coolant Temp.» and «Ambient Temper-

ature».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Coolant Temp.»

120°C (248°F) or more? Or, is

the value of «Coolant Temp.»

lower than «Ambient Tempera-

ture» by 15°C (27°F) or more?

Go to step 53. Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

53 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

Check the engine coolant temperature sensor.

<Ref. to FU(w/o STI)-94, INSPECTION, Engine

Coolant Temperature Sensor.>

Is the engine coolant tempera-

ture sensor normal?

Go to step 54. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

Step Check Yes No

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EN(w/o STI)(diag)-350

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

54 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

engine coolant temperature sensor.

3) Measure the resistance of harness between

ECM connector and engine coolant tempera-

ture sensor connector.

Connector & terminal

(E159) No. 27 — (E8) No. 1:

(E158) No. 38 — (E8) No. 2:

Is the resistance less than 1 Ω? Go to step 55. Repair the open

circuit of the har-

ness between the

ECM connector

and engine coolant

temperature sen-

sor connector.

55 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 38 — Engine ground:

(E159) No. 27 — Engine ground:

Is the resistance 1 MΩ or

more?

Even if DTC is

detected, it has

returned to a nor-

mal condition at

this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

Repair the short

circuit to ground in

harness between

ECM connector

and engine coolant

temperature sen-

sor connector.

56 CHECK IGNITION SYSTEM.

Check the ignition system. <Ref. to EN(w/o

STI)(diag)-80, IGNITION CONTROL SYSTEM,

Diagnostics for Engine Starting Failure.>

Is the ignition system normal? Go to step 57. Repair the ignition

system. <Ref. to

IG(w/o STI)-2,

General Descrip-

tion.>

Step Check Yes No

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EN(w/o STI)(diag)-351

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

57 CHECK FREEZE FRAME DATA.

1) Using Subaru Select Monitor, read the val-

ues of «Idle Mass Air Flow Feedback correct»,

«ISC Learning Value» and «Idle dirty throttle

correct» in freeze frame data.

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

2) Obtain the sum value of «Idle Mass Air Flow

Feedback correct», «ISC Learning Value» and

«Idle dirty throttle correct».

3) Start the engine and warm up completely.

4) Using Subaru Select Monitor, read the val-

ues of «Idle Mass Air Flow Feedback correct»,

«ISC Learning Value» and «Idle dirty throttle

correct» in current data at normal idling.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

5) Obtain the sum value of «Idle Mass Air Flow

Feedback correct», «ISC Learning Value» and

«Idle dirty throttle correct».

Is the sum value of freeze frame

data less than 80% of the sum

value of current data?

Go to step 58. Go to step 60.

58 CHECK AIR INTAKE SYSTEM.

Check the installing condition of the air intake

system.

Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

<Ref. to IN(w/o

STI)-2, General

Description.>

Go to step 59.

59 CHECK AIR INTAKE SYSTEM.

Check the air intake system related parts.

• Brake booster: <Ref. to BR-59, INSPEC-

TION, Brake Booster.>

• Mass air flow and intake air temperature sen-

sor: <Ref. to FU(w/o STI)-118, INSPECTION,

Mass Air Flow and Intake Air Temperature Sen-

sor.>

• PCV pipe: <Ref. to EC(w/o STI)-73, INSPEC-

TION, PCV Pipe.>

• PCV connector: <Ref. to EC(w/o STI)-75,

INSPECTION, PCV Connector.>

• PCV hose: <Ref. to EC(w/o STI)-77,

INSPECTION, PCV Hose.>

• PCV hose assembly: <Ref. to EC(w/o STI)-

79, INSPECTION, PCV Hose Assembly.>

• PCV valve: <Ref. to EC(w/o STI)-82,

INSPECTION, PCV Valve.>

• Purge control solenoid valve 1 and purge

control solenoid valve 2: <Ref. to EC(w/o STI)-

29, INSPECTION, Purge Control Solenoid

Valve.>

Are all of the air intake system

related parts normal?

Go to step 77. Replace the parts

if defective.

Step Check Yes No

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EN(w/o STI)(diag)-352

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

60 CHECK FREEZE FRAME DATA.

1) Using the Subaru Select Monitor, read the

values of the followings: «VVT Adv. Ang.

Amount R», «VVT Advance Target Angle

Amount R», «VVT Adv. Ang. Amount L», «VVT

Advance Target Angle Amount L», «Exh. VVT

Retard Ang. R», «Ex VVT Retard Target Angle

R», «Exh. VVT Retard Ang. L» and «Ex VVT

Retard Target Angle L».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

2) Using the Subaru Select Monitor, compare

the respective values between the followings:

«VVT Adv. Ang. Amount R» and «VVT Advance

Target Angle Amount R», «VVT Adv. Ang.

Amount L» and «VVT Advance Target Angle

Amount L», «Exh. VVT Retard Ang. R» and «Ex

VVT Retard Target Angle R», «Exh. VVT

Retard Ang. L» and «Ex VVT Retard Target

Angle L».

Does all of the advance angle

amount and retard angle

amount synchronize with their

target values?

Go to step 77. Diagnose the part

that does not syn-

chronize.

• Intake RH: Go to

step 61.

• Intake LH: Go to

step 65.

• Exhaust RH: Go

to step 69.

• Exhaust LH: Go

to step 73.

61 CHECK POWER SUPPLY TO THE INTAKE

OIL CONTROL SOLENOID RH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the intake oil

control solenoid RH.

3) Turn the ignition switch to ON.

4) Measure the voltage between intake oil con-

trol solenoid RH connector and engine ground.

Connector & terminal

(E38) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 62. Repair the power

supply circuit.

62 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID RH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and intake oil control solenoid

RH.

Connector & terminal

(E159) No. 7 — (E38) No. 2:

Is the resistance less than 1 Ω? Go to step 63. Repair the open

circuit in harness

between ECM con-

nector and intake

oil control solenoid

RH connector.

63 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID RH CON-

NECTOR.

Measure the resistance between intake oil con-

trol solenoid RH connector and engine ground.

Connector & terminal

(E38) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 64. Repair the short

circuit to ground in

harness between

ECM connector

and intake oil con-

trol solenoid RH

connector.

64 CHECK INTAKE OIL CONTROL SOLENOID

RH.

Check the intake oil control solenoid RH. <Ref.

to FU(w/o STI)-110, INSPECTION, Oil Control

Solenoid.>

Is the intake oil control solenoid

RH normal?

Replace the intake

cam sprocket RH.

<Ref. to ME(w/o

STI)-141, Cam

Sprocket.>

Replace the intake

oil control solenoid

RH. <Ref. to FU(w/

o STI)-108, Oil

Control Solenoid.>

Step Check Yes No

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EN(w/o STI)(diag)-353

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

65 CHECK POWER SUPPLY TO THE INTAKE

OIL CONTROL SOLENOID LH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the intake oil

control solenoid LH.

3) Turn the ignition switch to ON.

4) Measure the voltage between intake oil con-

trol solenoid LH connector and engine ground.

Connector & terminal

(E37) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 66. Repair the power

supply circuit.

66 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID LH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and intake oil control solenoid

LH.

Connector & terminal

(E159) No. 15 — (E37) No. 2:

Is the resistance less than 1 Ω? Go to step 67. Repair the open

circuit in harness

between ECM con-

nector and intake

oil control solenoid

LH connector.

67 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID LH CON-

NECTOR.

Measure the resistance between intake oil con-

trol solenoid LH connector and engine ground.

Connector & terminal

(E37) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 68. Repair the short

circuit to ground in

harness between

ECM connector

and intake oil con-

trol solenoid LH

connector.

68 CHECK INTAKE OIL CONTROL SOLENOID

LH.

Check the intake oil control solenoid LH. <Ref.

to FU(w/o STI)-110, INSPECTION, Oil Control

Solenoid.>

Is the intake oil control solenoid

LH normal?

Replace the intake

cam sprocket LH.

<Ref. to ME(w/o

STI)-141, Cam

Sprocket.>

Replace the intake

oil control solenoid

LH. <Ref. to FU(w/

o STI)-108, Oil

Control Solenoid.>

69 CHECK POWER SUPPLY TO THE EXHAUST

OIL CONTROL SOLENOID RH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the exhaust

oil control solenoid RH.

3) Turn the ignition switch to ON.

4) Measure the voltage between exhaust oil

control solenoid RH connector and engine

ground.

Connector & terminal

(E63) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 70. Repair the power

supply circuit.

70 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID RH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and exhaust oil control solenoid

RH.

Connector & terminal

(E159) No. 23 — (E63) No. 2:

Is the resistance less than 1 Ω? Go to step 71. Repair the open

circuit in harness

between ECM con-

nector and exhaust

oil control solenoid

RH connector.

Step Check Yes No

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EN(w/o STI)(diag)-354

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

71 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID RH CON-

NECTOR.

Measure the resistance between exhaust oil

control solenoid RH connector and engine

ground.

Connector & terminal

(E63) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 72. Repair the short

circuit to ground in

harness between

ECM connector

and exhaust oil

control solenoid

RH connector.

72 CHECK EXHAUST OIL CONTROL SOLE-

NOID RH.

Check the exhaust oil control solenoid RH.

<Ref. to FU(w/o STI)-110, INSPECTION, Oil

Control Solenoid.>

Is the exhaust oil control sole-

noid RH normal?

Replace the

exhaust cam

sprocket RH. <Ref.

to ME(w/o STI)-

141, Cam

Sprocket.>

Replace the

exhaust oil control

solenoid RH. <Ref.

to FU(w/o STI)-

108, Oil Control

Solenoid.>

73 CHECK POWER SUPPLY TO THE EXHAUST

OIL CONTROL SOLENOID LH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the exhaust

oil control solenoid LH.

3) Turn the ignition switch to ON.

4) Measure the voltage between exhaust oil

control solenoid LH connector and engine

ground.

Connector & terminal

(E66) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 74. Repair the power

supply circuit.

74 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID LH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and exhaust oil control solenoid

LH.

Connector & terminal

(E159) No. 31 — (E66) No. 2:

Is the resistance less than 1 Ω? Go to step 75. Repair the open

circuit in harness

between ECM con-

nector and exhaust

oil control solenoid

LH connector.

75 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID LH CON-

NECTOR.

Measure the resistance between exhaust oil

control solenoid LH connector and engine

ground.

Connector & terminal

(E66) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 76. Repair the short

circuit to ground in

harness between

ECM connector

and exhaust oil

control solenoid

LH connector.

76 CHECK EXHAUST OIL CONTROL SOLE-

NOID LH.

Check the exhaust oil control solenoid LH.

<Ref. to FU(w/o STI)-110, INSPECTION, Oil

Control Solenoid.>

Is the exhaust oil control sole-

noid LH normal?

Replace the

exhaust cam

sprocket LH. <Ref.

to ME(w/o STI)-

141, Cam

Sprocket.>

Replace the

exhaust oil control

solenoid LH. <Ref.

to FU(w/o STI)-

108, Oil Control

Solenoid.>

77 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

Check the engine coolant temperature sensor.

<Ref. to FU(w/o STI)-94, INSPECTION, Engine

Coolant Temperature Sensor.>

Is the engine coolant tempera-

ture sensor normal?

Go to step 78. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 354 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-355

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

78 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

engine coolant temperature sensor.

3) Measure the resistance of harness between

ECM connector and engine coolant tempera-

ture sensor connector.

Connector & terminal

(E159) No. 27 — (E8) No. 1:

(E158) No. 38 — (E8) No. 2:

Is the resistance less than 1 Ω? Go to step 79. Repair the open

circuit of the har-

ness between the

ECM connector

and engine coolant

temperature sen-

sor connector.

79 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 38 — Engine ground:

(E159) No. 27 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 80. Repair the short

circuit to ground in

harness between

ECM connector

and engine coolant

temperature sen-

sor connector.

80 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

Check the mass air flow and intake air tempera-

ture sensor. <Ref. to FU(w/o STI)-118,

INSPECTION, Mass Air Flow and Intake Air

Temperature Sensor.>

Is the mass air flow and intake

air temperature sensor normal?

Go to step 81. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

81 CHECK MANIFOLD ABSOLUTE PRESSURE

AND INTAKE AIR TEMPERATURE SENSOR.

Check the manifold absolute pressure and

intake air temperature sensor. <Ref. to FU(w/o

STI)-121, INSPECTION, Manifold Absolute

Pressure and Intake Air Temperature Sensor.>

Is the manifold absolute pres-

sure and intake air temperature

sensor normal?

Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Check the manifold

absolute pressure

and intake air tem-

perature sensor.

<Ref. to FU(w/o

STI)-120, Manifold

Absolute Pressure

and Intake Air

Temperature Sen-

sor.>

82 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

fuel injectors.

3) Measure the resistance of harness between

ECM connector and fuel injector connector.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 83. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

Step Check Yes No

15WRX_STI_US_EN.book 355 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-356

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

83 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 84. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

84 CHECK IGNITION SYSTEM.

Check the ignition system. <Ref. to EN(w/o

STI)(diag)-80, IGNITION CONTROL SYSTEM,

Diagnostics for Engine Starting Failure.>

Is the ignition system normal? Go to step 85. Repair the ignition

system. <Ref. to

IG(w/o STI)-2,

General Descrip-

tion.>

85 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «A/C Compressor Signal» and «Idle A/C

load correct».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Does the value of «A/C Com-

pressor Signal» indicate ON

output, and does the value of

«Idle A/C load correct»

increase?

Check the air con-

ditioner. <Ref. to

AC(diag)-12,

INSPECTION,

Diagnostics with

Phenomenon.>

<Ref. to AC(diag)-

2, PROCEDURE,

Basic Diagnostic

Procedure.>

Go to step 86.

86 CHECK FREEZE FRAME DATA.

1) Using the Subaru Select Monitor, read the

value of «Electric Load Feedback Val».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

2) Compare the value of «Electric Load Feed-

back Val» with that of «ISC Learning Value»,

which is described in “Engine Current Data Dis-

play”. <Ref. to EN(w/o STI)(diag)-37, DISPLAY

CURRENT ENGINE DATA, OPERATION, Sub-

aru Select Monitor.>

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Is the value of «Electric Load

Feedback Val» 20% or more of

«ISC Learning Value»?

Check the genera-

tor and power

assisted system.

<Ref. to SC(w/o

STI)-45, INSPEC-

TION, Generator.>

<Ref. to PS(diag)-

2, Basic Diagnostic

Procedure.>

Go to step 87.

87 CHECK FREEZE FRAME DATA.

1) Using the Subaru Select Monitor, read the

values of «Vehicle Speed», «Engine Speed»

and «AT turbine speed».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is there any freeze frame data

indicating that the value of

«Vehicle Speed» is less than 30

km/h (18.6 MPH), and that the

difference in values between

«Engine Speed» and «AT tur-

bine speed» is less than 100

rpm?

Repair the CVT.

<Ref. to

CVT(TR690)-3,

General Descrip-

tion.>

Go to step 88.

Step Check Yes No

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EN(w/o STI)(diag)-357

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

88 CHECK DTC. Is DTC of CVT displayed?

<Ref. to CVT(diag)-16, OPER-

ATION, Read Diagnostic Trou-

ble Code (DTC).>

Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to

CVT(diag)-32, List

of Diagnostic Trou-

ble Code (DTC).>

Even if DTC is

detected, it has

returned to a nor-

mal condition at

this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

89 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Calculated load value» and «Relative

Throttle Pos.».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Calculated load

value» decreasing while that of

«Relative Throttle Pos.» is

increasing?

Go to step 90. Go to step 94.

90 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

Check the mass air flow and intake air tempera-

ture sensor. <Ref. to FU(w/o STI)-118,

INSPECTION, Mass Air Flow and Intake Air

Temperature Sensor.>

Is the mass air flow and intake

air temperature sensor normal?

Go to step 91. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

91 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the mass air flow and intake air temperature

sensor.

3) Measure the resistance of harness between

ECM connector and the mass air flow and

intake air temperature sensor connector.

Connector & terminal

(B134) No. 16 — (B3) No. 3:

(B134) No. 28 — (B3) No. 2:

Is the resistance less than 1 Ω? Go to step 92. Repair the open

circuit of harness

between ECM con-

nector and the

mass air flow and

intake air tempera-

ture sensor con-

nector.

92 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(B134) No. 16 — Engine ground:

(B134) No. 28 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 93. Repair the ground

short circuit of har-

ness between

ECM connector

and the mass air

flow and intake air

temperature sen-

sor connector.

Step Check Yes No

15WRX_STI_US_EN.book 357 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-358

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

93 CHECK CURRENT DATA.

1) Start the engine and warm up completely.

2) Using the Subaru Select Monitor, read the

value of «Calculated load value», then compare

it with that of «Calculated load value» listed in

“Engine Current Data Display”. <Ref. to EN(w/o

STI)(diag)-37, DISPLAY CURRENT ENGINE

DATA, OPERATION, Subaru Select Monitor.>

NOTE:

• The value of «Calculated load value» change

depending on how the engine internal parts set-

tle in. If the value is out of standard, judge it

again by comparing the vehicle with another

one with the same specifications and similar

conditions such as travel distance.

• For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Does the value of «Calculated

load value» falls between 90 —

110% of the value described in

the list?

Go to step 94. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

94 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

fuel injectors.

3) Measure the resistance of harness between

ECM connector and fuel injector connector.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 95. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

95 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 96. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

96 CHECK IGNITION SYSTEM.

Check the ignition system. <Ref. to EN(w/o

STI)(diag)-80, IGNITION CONTROL SYSTEM,

Diagnostics for Engine Starting Failure.>

Is the ignition system normal? Go to step 97. Repair the ignition

system. <Ref. to

IG(w/o STI)-2,

General Descrip-

tion.>

Step Check Yes No

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EN(w/o STI)(diag)-359

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

97 CHECK OF FUEL PUMP.

1) Select «Fuel Pump» from “Actuator ON/

OFF Operation” in “System Operation Check

Mode”.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

2) Check if operating sound occurs in the fuel

pump according to ON/OFF switching opera-

tion.

Does the fuel pump emit oper-

ating sound?

Go to step 99. Go to step 98.

98 CHECK OF FUEL PUMP.

Check fuel pump. <Ref. to FU(w/o STI)-172,

INSPECTION, Fuel Pump.>

Is the fuel pump normal? Check fuel pump

system. <Ref. to

EN(w/o STI)(diag)-

209, DTC P0230

FUEL PUMP PRI-

MARY CIRCUIT,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).>

Replace the fuel

pump. <Ref. to

FU(w/o STI)-168,

Fuel Pump.>

99 CHECK FUEL TANK.

Check if any foreign matters such as iron pow-

der exist in the fuel tank.

Is there any foreign matter in

the fuel tank?

Remove foreign

matter from the

fuel tank.

Go to step 100.

100 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 340 —

400 kPa (3.5 — 4.1 kgf/cm

, 49

— 58 psi)?

Go to step 101. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

101 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Fuel Rail Pressure A» and «Com-

manded Fuel Rail Pressure A».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value in «Fuel Rail Pres-

sure A» synchronized with the

one in «Commanded Fuel Rail

Pressure A» in all freeze frame

data?

Go to step 102. Check the high-

pressure fuel

pump. <Ref. to

FU(w/o STI)-82,

INSPECTION,

High Pressure

Fuel Pump.>

102 CHECK ENGINE RUNNING CONDITION.

Check the engine running condition using

“Roughness monitor” in the Subaru Select

Monitor.

NOTE:

For detailed operation procedures, refer to “PC

application help for Subaru Select Monitor”.

Is there a large difference in the

speed between each cylinder?

It is possible that

the compression

pressure of the

engine is not suffi-

cient. Check the

engine. <Ref. to

ME(w/o STI)-352,

INSPECTION,

Engine Trouble in

General.>

Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Step Check Yes No

15WRX_STI_US_EN.book 359 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-360

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EY:DTC P1604 STARTABILITY MALFUNCTION

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-181, DTC P1604 STARTABILITY MALFUNCTION, Di-

agnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode. <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>

NOTE:

This DTC may be detected even if fault does not occur in the vehicle. If the customer does not ask for in-

spection, perform the clear memory mode without inspection and return the vehicle to the user.

15WRX_STI_US_EN.book 360 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-361

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

EN-10805

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

E158

E10

B22

5678

10 11 12

1413 15 16

E10

213

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

ECM

SBF-7

232221 262524201918

587

10 11

B550

(BLACK)

CRANKSHAFT

POSITION SENSOR

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 361 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-362

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 362 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-363

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

ECM

E34

E32

E33

E31

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

B220

B550

216

E3B22

E31

E159

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10793

E32

E33

E34

232221 262524201918

587

10 11

B550

SBF-7

IGNITION COIL No. 4

IGNITION COIL No. 3

IGNITION COIL No. 2

IGNITION COIL No. 1

BATTERY

FUSE HOLDER

IG RELAY

(GRAY)

15WRX_STI_US_EN.book 363 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-364

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E3B22

B550

215

B220

E38E37

E38

EN-10796

E159

215

E37

SBF-7

ECM

232221 262524201918

587

10 11

B550

INTAKE

OIL CONTROL

SOLENOID LH

INTAKE

OIL CONTROL

SOLENOID RH

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

ECM

17 18

25 26

19 20

27 28

E159

B22

5678

10 11 12

1413 15 16

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E3B22

B550

215

B220

E66E63

E63

223

EN-10795

E159

231

E66

SBF-7

232221 262524201918

587

10 11

B550

EXHAUST

OIL CONTROL

SOLENOID LH

EXHAUST

OIL CONTROL

SOLENOID RH

MAIN RELAY

BATTERY

FUSE HOLDER

(GRAY)

15WRX_STI_US_EN.book 364 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-365

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

B22

5678

10 11 12

1413 15 16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E3 B22

B122

EN-10799

123

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B122

J/C

B550

215

B220

B134A:

E158B:

A19

A16

A28

SBF-7

ECM

232221 262524201918

587

10 11

B550

: TERMINAL No. OPTIONAL

ARRANGEMENT

MAIN RELAY

BATTERY

FUSE HOLDER

MASS AIR FLOW &

INTAKE AIR TEMPERATURE SENSOR

(BROWN)

(BLACK)

E158B:

E159C:

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

C27

B38

EN-10322

ECM

ENGINE COOLANT

TEMPERATURE

SENSOR

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 365 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-366

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

B22

EN-10806

B550

215

B220

E36

E35

213

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E158

E35

E36

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BLACK)

INTAKE CAMSHAFT

POSITION SENSOR RH

INTAKE CAMSHAFT

POSITION SENSOR LH

MAIN RELAY

BATTERY

FUSE HOLDER

B22

EN-10807

B550

215

B220

E65

E62

213

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

E158

E65

E62

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

232221 262524201918

587

10 11

B550

SBF-7

ECM

(BLACK)

EXHAUST CAMSHAFT

POSITION SENSOR RH

EXHAUST CAMSHAFT

POSITION SENSOR LH

MAIN RELAY

BATTERY

FUSE HOLDER

15WRX_STI_US_EN.book 366 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-367

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK DTC. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Go to step 2.

2 CHECK IMMOBILIZER.

Check the immobilizer. <Ref. to IM(diag)-2,

Basic Diagnostic Procedure.>

Is the immobilizer normal? Go to step 3. Repair the immobi-

lizer. <Ref. to

IM(diag)-2, Basic

Diagnostic Proce-

dure.>

3 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Is it possible to reproduce the

faulty phenomenon or to iden-

tify the faulty condition?

Go to step 30. Go to step 4.

4 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Engine Speed» and «Control module

voltage».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Engine Speed»

0 rpm?

• When the value

of «Control module

voltage» is less

than 5 V: Check

the battery. <Ref.

to SC(w/o STI)-51,

INSPECTION,

Battery.>

• When the value

of «Control module

voltage» is 5 V or

more: Go to step 5.

• When the value

of «Engine Speed»

is less than 250

rpm: Go to step 12.

• When the value

of «Engine Speed»

is 250 rpm or more:

Go to step 20.

5 CHECK FREEZE FRAME DATA.

Read the value of «Control module voltage»

using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Control module

voltage» less than 9 V?

It is possible that

the engine friction

is too large. Check

the engine. <Ref.

to ME(w/o STI)-

352, INSPEC-

TION, Engine

Trouble in Gen-

eral.>

• When the value

of «Control module

voltage» changes

in any one of

freeze frame data:

Go to step 6.

• When the value

of «Control module

voltage» does not

change in all

freeze frame data:

Check the starter

motor circuit. <Ref.

to EN(w/o

STI)(diag)-67,

STARTER MOTOR

CIRCUIT, Diag-

nostics for Engine

Starting Failure.>

6 CHECK INSTALLATION CONDITION OF

CRANKSHAFT POSITION SENSOR.

Is the crankshaft position sen-

sor installed correctly?

Go to step 7. Install the crank-

shaft position sen-

sor correctly. <Ref.

to FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

15WRX_STI_US_EN.book 367 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-368

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

7 CHECK CRANKSHAFT POSITION SENSOR.

Check the crankshaft position sensor. <Ref. to

FU(w/o STI)-100, INSPECTION, Crankshaft

Position Sensor.>

Is the crankshaft position sen-

sor normal?

Go to step 8. Replace the crank-

shaft position sen-

sor. <Ref. to FU(w/

o STI)-98, Crank-

shaft Position Sen-

sor.>

8 CHECK POWER SUPPLY TO CRANKSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the crank-

shaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 9. Repair the power

supply circuit.

9 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and crankshaft position sensor

connector.

Connector & terminal

(E158) No. 19 — (E10) No. 2:

(E158) No. 31 — (E10) No. 3:

Is the resistance less than 1 Ω? Go to step 10. Repair the open

circuit in the har-

ness between the

ECM connector

and crankshaft

position sensor

connector.

10 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

Measure the resistance between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 2 — Engine ground:

(E10) No. 3 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 11. Repair short cir-

cuit to ground in

harness between

ECM connector

and crankshaft

position sensor

connector.

11 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the crankshaft position sensor.

<Ref. to FU(w/o STI)-98, Crankshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

12 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Coolant Temp.», «Ambient Tempera-

ture» and «Fuel Pump Duty».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Coolant Temp.»

120°C (248°F) or more? Or, is

the value of «Coolant Temp.»

lower than «Ambient Tempera-

ture» by 15°C (27°F) or more?

Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

• When the value

of «Fuel Pump

Duty» is 60% or

more: Go to step

13.

• When the value

of «Fuel Pump

Duty» is less than

60%: Check the

fuel pump system.

<Ref. to EN(w/o

STI)(diag)-209,

DTC P0230 FUEL

PUMP PRIMARY

CIRCUIT, Diag-

nostic Procedure

with Diagnostic

Trouble Code

(DTC).>

Step Check Yes No

15WRX_STI_US_EN.book 368 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-369

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

13 CHECK OF FUEL PUMP.

1) Select «Fuel Pump» from “Actuator ON/

OFF Operation” in “System Operation Check

Mode”.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

2) Check if operating sound occurs in the fuel

pump according to ON/OFF switching opera-

tion.

Does the fuel pump emit oper-

ating sound?

Go to step 15. Go to step 14.

14 CHECK OF FUEL PUMP.

Check fuel pump. <Ref. to FU(w/o STI)-172,

INSPECTION, Fuel Pump.>

Is the fuel pump normal? Check fuel pump

system. <Ref. to

EN(w/o STI)(diag)-

209, DTC P0230

FUEL PUMP PRI-

MARY CIRCUIT,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).>

Replace the fuel

pump. <Ref. to

FU(w/o STI)-168,

Fuel Pump.>

15 CHECK FUEL TANK.

Check if any foreign matters such as iron pow-

der exist in the fuel tank.

Is there any foreign matter in

the fuel tank?

Remove foreign

matter from the

fuel tank.

Go to step 16.

16 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 340 —

400 kPa (3.5 — 4.1 kgf/cm

, 49

— 58 psi)?

Go to step 17. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

17 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Fuel Rail Pressure A» and «Com-

manded Fuel Rail Pressure A».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value in «Fuel Rail Pres-

sure A» synchronized with the

one in «Commanded Fuel Rail

Pressure A» in all freeze frame

data?

Go to step 18. Check the high-

pressure fuel

pump. <Ref. to

FU(w/o STI)-82,

INSPECTION,

High Pressure

Fuel Pump.>

Step Check Yes No

15WRX_STI_US_EN.book 369 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-370

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

18 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

fuel injectors.

3) Measure the resistance of harness between

ECM connector and fuel injector connector.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 19. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

19 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 29. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

20 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Coolant Temp.», «Ambient Tempera-

ture» and «Engine Speed».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Coolant Temp.»

120°C (248°F) or more? Or, is

the value of «Coolant Temp.»

lower than «Ambient Tempera-

ture» by 15°C (27°F) or more?

Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

• When the mini-

mum value of

«Engine Speed» is

less than 300 rpm:

Go to step 21.

• When the mini-

mum value of

«Engine Speed» is

300 rpm or more: It

is possible that the

engine compres-

sion pressure is

not sufficient.

Check the engine.

<Ref. to ME(w/o

STI)-352,

INSPECTION,

Engine Trouble in

General.>

21 CHECK FUEL INJECTOR.

Check fuel injector. <Ref. to FU(w/o STI)-70,

INSPECTION, Fuel Injector.>

Is there any deposit in the fuel

injectors?

Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

Go to step 22.

22 CHECK FUEL TANK.

Check if any foreign matters such as iron pow-

der exist in the fuel tank.

Is there any foreign matter in

the fuel tank?

Remove foreign

matter from the

fuel tank.

Go to step 23.

Step Check Yes No

15WRX_STI_US_EN.book 370 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-371

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

23 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the value

in «Coolant Temp.».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value of «Coolant Temp.»

40 — 90°C (104 — 194°F)?

Go to step 25. Go to step 24.

24 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure five minutes after the

engine is stopped. <Ref. to ME(w/o STI)-31,

INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

NOTE:

If the engine does not start, measure the fuel

pressure five minutes after cranking is complet-

ed.

Is the measured value 147 kPa

(1.5 kgf/cm

, 21 psi) or more?

Go to step 29. Replace the pres-

sure regulator.

<Ref. to FU(w/o

STI)-183, Fuel Fil-

ter.>

25 CHECK FUEL INJECTOR.

1) After the engine is stopped, scavenge inside

of the intake manifold by applying compressed

air.

2) Measure the HC concentration inside the

intake manifold 15 minutes after scavenging is

completed.

Is the HC concentration less

than 4,000 ppm?

Go to step 27. Go to step 26.

26 CHECK FUEL INJECTOR.

Check fuel injector. <Ref. to FU(w/o STI)-70,

INSPECTION, Fuel Injector.>

Are fuel injectors OK? Go to step 27. Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

27 CHECK THROTTLE BODY.

Check throttle body. <Ref. to FU(w/o STI)-16,

INSPECTION, Throttle Body.>

Is there any deposit in the throt-

tle body?

Replace the throt-

tle body. <Ref. to

FU(w/o STI)-15,

Throttle Body.>

Go to step 28.

28 CHECK AIR INTAKE SYSTEM.

Check the installing condition of the air intake

system.

Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

<Ref. to IN(w/o

STI)-2, General

Description.>

Go to step 29.

29 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Go to step 30.

Step Check Yes No

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EN(w/o STI)(diag)-372

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

30 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Does cranking occur? • When the engine

speed is abnormal

during cranking:

Go to step 37.

• When an initial

combustion does

not occur: Go to

step 40.

• When the engine

stalls immediately

after engine start:

Go to step 57.

• When the engine

takes time to start:

Go to step 80.

Go to step 31.

31 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Does the sound occur by a pro-

truding starter pinion gear dur-

ing cranking?

• When the starter

motor does not

rotate: Go to step

32.

• When the starter

motor rotates but

does not engage:

Go to step 34.

Go to step 35.

32 CHECK BATTERY.

Check the battery. <Ref. to SC(w/o STI)-51,

INSPECTION, Battery.>

Is the battery OK? Go to step 33. Charge or replace

the battery. <Ref.

to SC(w/o STI)-50,

Battery.>

33 CHECK ENGINE MAIN BODY.

Using the ST, rotate the crankshaft.

ST 18252AA000 CRANKSHAFT

SOCKET

Does the crankshaft rotate

smoothly?

Check the starter

motor. <Ref. to

SC(w/o STI)-24,

INSPECTION,

Starter.>

NOTE:

It is possible that

the engine friction

increased tempo-

rarily. Check if any

foreign matter is

mixed in engine oil.

If a foreign matter

is found, check the

engine. <Ref. to

ME(w/o STI)-352,

INSPECTION, En-

gine Trouble in

General.>

It is possible that

the engine friction

is too large. Check

the engine. <Ref.

to ME(w/o STI)-

352, INSPEC-

TION, Engine

Trouble in Gen-

eral.>

34 CHECK STARTER MOTOR.

Check the starter motor. <Ref. to SC(w/o STI)-

24, INSPECTION, Starter.>

Is there any wear or damage in

the starter pinion gear?

Repair the starter

motor. <Ref. to

SC(w/o STI)-7,

Starter.>

•CVT model:

Replace the torque

converter assem-

bly. <Ref. to

CVT(TR690)-140,

Torque Converter

Assembly.>

• MT model:

Replace the fly-

wheel. <Ref. to CL-

15, Flywheel.>

Step Check Yes No

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EN(w/o STI)(diag)-373

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

35 CHECK BATTERY.

Check the battery. <Ref. to SC(w/o STI)-51,

INSPECTION, Battery.>

Is the battery OK? Go to step 36. Charge or replace

the battery. <Ref.

to SC(w/o STI)-50,

Battery.>

36 CHECK STARTER MOTOR.

Check the starter motor. <Ref. to SC(w/o STI)-

24, INSPECTION, Starter.>

Is the starter motor OK? Check the starter

motor circuit. <Ref.

to EN(w/o

STI)(diag)-67,

STARTER MOTOR

CIRCUIT, Diag-

nostics for Engine

Starting Failure.>

Repair the starter

motor. <Ref. to

SC(w/o STI)-7,

Starter.>

37 CHECK CURRENT DATA.

Read the value of «Engine Speed» during

cranking using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Is the value of «Engine Speed»

300 rpm or more?

It is possible that

the compression

pressure of the

engine is not suffi-

cient. Check the

engine. <Ref. to

ME(w/o STI)-352,

INSPECTION,

Engine Trouble in

General.>

Go to step 38.

38 CHECK BATTERY.

Check the battery. <Ref. to SC(w/o STI)-51,

INSPECTION, Battery.>

Is the battery OK? Go to step 39. Charge or replace

the battery. <Ref.

to SC(w/o STI)-50,

Battery.>

39 CHECK ENGINE MAIN BODY.

Using the ST, rotate the crankshaft.

ST 18252AA000 CRANKSHAFT

SOCKET

Does the crankshaft rotate

smoothly?

Check the starter

motor. <Ref. to

SC(w/o STI)-24,

INSPECTION,

Starter.>

NOTE:

It is possible that

the engine friction

increased tempo-

rarily. Check if any

foreign matter is

mixed in engine oil.

If a foreign matter

is found, check the

engine. <Ref. to

ME(w/o STI)-352,

INSPECTION, En-

gine Trouble in

General.>

It is possible that

the engine friction

is too large. Check

the engine. <Ref.

to ME(w/o STI)-

352, INSPEC-

TION, Engine

Trouble in Gen-

eral.>

40 CHECK OPERATION OF EACH FUEL INJEC-

TOR.

Using a sound scope, check each fuel injector

for operation sound during cranking.

Does the fuel injector emit

operating sound?

Go to step 41. Go to step 54.

Step Check Yes No

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EN(w/o STI)(diag)-374

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

41 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 340 —

400 kPa (3.5 — 4.1 kgf/cm

, 49

— 58 psi)?

Go to step 42. Go to step 52.

42 CHECK IGNITION CONDITION.

Check the ignition condition. <Ref. to EN(w/o

STI)(diag)-80, IGNITION CONTROL SYSTEM,

Diagnostics for Engine Starting Failure.>

Is the ignition condition nor-

mal?

Go to step 43. Go to step 46.

43 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Check for the condition of fault occurrence.

Does the fault occur only within

approx. 15 to 120 minutes after

the engine is stopped?

Go to step 45. • When the fault

occurs in two or

three minutes or a

long time after the

engine is stopped:

Go to step 44.

• When the fault

occurrence pat-

tern is inconsis-

tent: Go to step 94.

44 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure five minutes after the

engine is stopped. <Ref. to ME(w/o STI)-31,

INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

NOTE:

If the engine does not start, measure the fuel

pressure five minutes after cranking is complet-

ed.

Is the measured value 147 kPa

(1.5 kgf/cm

, 21 psi) or more?

Go to step 94. Replace the pres-

sure regulator.

<Ref. to FU(w/o

STI)-183, Fuel Fil-

ter.>

45 CHECK FUEL INJECTOR.

1) After the engine is stopped, scavenge inside

of the intake manifold by applying compressed

air.

2) Measure the HC concentration inside the

intake manifold 15 minutes after scavenging is

completed.

Is the HC concentration less

than 4,000 ppm?

Go to step 94. Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

46 CHECK SPARK PLUG.

Check the spark plug. <Ref. to IG(w/o STI)-8,

INSPECTION, Spark Plug.>

Are the spark plugs normal? Go to step 47. Replace all spark

plugs on all cylin-

ders. <Ref. to

IG(w/o STI)-4,

Spark Plug.>

Step Check Yes No

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EN(w/o STI)(diag)-375

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

47 CHECK CURRENT DATA.

Record the value of «Engine Speed» during

cranking using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Does the recorded value of

«Engine Speed» contain data

of 0 rpm?

It is possible that

temporary fault

occurs in the

crankshaft posi-

tion sensor circuit.

Check the crank-

shaft position sen-

sor circuit. <Ref. to

EN(w/o STI)(diag)-

236, DTC P0335

CRANKSHAFT

POSITION SEN-

SOR “A” CIRCUIT,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).>

Go to step 48.

48 CHECK IGNITION COIL POWER SUPPLY

CIRCUIT.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ignition coil.

3) Turn the ignition switch to ON.

4) Measure the voltage between ignition coil

connector and engine ground.

Connector & terminal

(E31) No. 1 (+) — Engine ground (–):

(E32) No. 1 (+) — Engine ground (–):

(E33) No. 1 (+) — Engine ground (–):

(E34) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 49. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in power

supply circuit

• Poor contact of

coupling connector

• Blown out of fuse

49 CHECK HARNESS BETWEEN ECM AND IG-

NITION COIL CONNECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance of harness between

ECM connector and ignition coil connector.

Connector & terminal

(E159) No. 8 — (E31) No. 2:

(E159) No. 16 — (E32) No. 2:

(E159) No. 24 — (E33) No. 2:

(E159) No. 32 — (E34) No. 2:

Is the resistance less than 1 Ω? Go to step 50. Repair the open

circuit in harness

between ECM con-

nector and ignition

coil connector.

50 CHECK HARNESS BETWEEN ECM AND IG-

NITION COIL CONNECTOR.

Measure the resistance of harness between

ECM connector and engine ground.

Connector & terminal

(E159) No. 8 — Engine ground:

(E159) No. 16 — Engine ground:

(E159) No. 24 — Engine ground:

(E159) No. 32 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 51. Repair the ground

short circuit of har-

ness between

ECM connector

and ignition coil

connector.

51 CHECK HARNESS OF IGNITION COIL

GROUND CIRCUIT.

1) Turn the ignition switch to OFF.

2) Measure the resistance of harness between

ignition coil connector and engine ground.

Connector & terminal

(E31) No. 3 — Engine ground:

(E32) No. 3 — Engine ground:

(E33) No. 3 — Engine ground:

(E34) No. 3 — Engine ground:

Is the resistance less than 5 Ω? Replace the igni-

tion coil. <Ref. to

IG(w/o STI)-11,

Ignition Coil.> If the

fault occurs after

servicing, con-

tinue the diagno-

sis. Go to step 99.

Repair the open

circuit in harness

between ignition

coil connector and

engine grounding

terminal.

Step Check Yes No

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EN(w/o STI)(diag)-376

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

52 CHECK OF FUEL PUMP.

1) Select «Fuel Pump» from “Actuator ON/

OFF Operation” in “System Operation Check

Mode”.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

2) Check if operating sound occurs in the fuel

pump according to ON/OFF switching opera-

tion.

Does the fuel pump emit oper-

ating sound?

Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

Go to step 53.

53 CHECK OF FUEL PUMP.

Check fuel pump. <Ref. to FU(w/o STI)-172,

INSPECTION, Fuel Pump.>

Is the fuel pump normal? Check fuel pump

system. <Ref. to

EN(w/o STI)(diag)-

209, DTC P0230

FUEL PUMP PRI-

MARY CIRCUIT,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).> If the fault

occurs after servic-

ing, continue the

diagnosis. Go to

step 94.

Replace the fuel

pump. <Ref. to

FU(w/o STI)-168,

Fuel Pump.>

54 CHECK CURRENT DATA.

Record the value of «Engine Speed» during

cranking using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Does the recorded value of

«Engine Speed» contain data

of 0 rpm?

It is possible that

temporary fault

occurs in the

crankshaft posi-

tion sensor circuit.

Check the crank-

shaft position sen-

sor circuit. <Ref. to

EN(w/o STI)(diag)-

236, DTC P0335

CRANKSHAFT

POSITION SEN-

SOR “A” CIRCUIT,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).>

Go to step 55.

55 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

fuel injectors.

3) Measure the resistance of harness between

ECM connector and fuel injector connector.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 56. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

Step Check Yes No

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EN(w/o STI)(diag)-377

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

56 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

57 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

Check the mass air flow and intake air tempera-

ture sensor. <Ref. to FU(w/o STI)-118,

INSPECTION, Mass Air Flow and Intake Air

Temperature Sensor.>

Is the mass air flow and intake

air temperature sensor normal?

Go to step 58. Go to step 78.

58 CHECK AIR INTAKE SYSTEM.

Check the installing condition of the air intake

system.

Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

<Ref. to IN(w/o

STI)-2, General

Description.>

Go to step 59.

59 CHECK ELECTRONIC THROTTLE CON-

TROL.

1) Disconnect the connectors from electronic

throttle control.

2) Start the engine with the electronic throttle

control connector disconnected.

Does the engine start? Go to step 60. Go to step 61.

60 CHECK THROTTLE BODY.

Check throttle body. <Ref. to FU(w/o STI)-16,

INSPECTION, Throttle Body.>

Is there any deposit in the throt-

tle body?

Replace the throt-

tle body. <Ref. to

FU(w/o STI)-15,

Throttle Body.>

Go to step 61.

61 CHECK FREEZE FRAME DATA.

1) Using the Subaru Select Monitor, read the

values of the followings: «VVT Adv. Ang.

Amount R», «VVT Advance Target Angle

Amount R», «VVT Adv. Ang. Amount L», «VVT

Advance Target Angle Amount L», «Exh. VVT

Retard Ang. R», «Ex VVT Retard Target Angle

R», «Exh. VVT Retard Ang. L» and «Ex VVT

Retard Target Angle L».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

2) Using the Subaru Select Monitor, compare

the respective values between the followings:

«VVT Adv. Ang. Amount R» and «VVT Advance

Target Angle Amount R», «VVT Adv. Ang.

Amount L» and «VVT Advance Target Angle

Amount L», «Exh. VVT Retard Ang. R» and «Ex

VVT Retard Target Angle R», «Exh. VVT

Retard Ang. L» and «Ex VVT Retard Target

Angle L».

Does all of the advance angle

amount and retard angle

amount synchronize with their

target values?

Go to step 112. Diagnose the part

where there is dif-

ference of 10 deg

or more.

• Intake RH: Go to

step 62.

• Intake LH: Go to

step 66.

• Exhaust RH: Go

to step 70.

• Exhaust LH: Go

to step 74.

Step Check Yes No

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EN(w/o STI)(diag)-378

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

62 CHECK POWER SUPPLY TO THE INTAKE

OIL CONTROL SOLENOID RH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the intake oil

control solenoid RH.

3) Turn the ignition switch to ON.

4) Measure the voltage between intake oil con-

trol solenoid RH connector and engine ground.

Connector & terminal

(E38) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 63. Repair the power

supply circuit.

63 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID RH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and intake oil control solenoid

RH.

Connector & terminal

(E159) No. 7 — (E38) No. 2:

Is the resistance less than 1 Ω? Go to step 64. Repair the open

circuit in harness

between ECM con-

nector and intake

oil control solenoid

RH connector.

64 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID RH CON-

NECTOR.

Measure the resistance between intake oil con-

trol solenoid RH connector and engine ground.

Connector & terminal

(E38) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 65. Repair the short

circuit to ground in

harness between

ECM connector

and intake oil con-

trol solenoid RH

connector.

65 CHECK INTAKE OIL CONTROL SOLENOID

RH.

Check the intake oil control solenoid RH. <Ref.

to FU(w/o STI)-110, INSPECTION, Oil Control

Solenoid.>

Is the intake oil control solenoid

RH normal?

Replace the intake

cam sprocket RH.

<Ref. to ME(w/o

STI)-141, Cam

Sprocket.>

Replace the intake

oil control solenoid

RH. <Ref. to FU(w/

o STI)-108, Oil

Control Solenoid.>

66 CHECK POWER SUPPLY TO THE INTAKE

OIL CONTROL SOLENOID LH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the intake oil

control solenoid LH.

3) Turn the ignition switch to ON.

4) Measure the voltage between intake oil con-

trol solenoid LH connector and engine ground.

Connector & terminal

(E37) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 67. Repair the power

supply circuit.

67 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID LH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and intake oil control solenoid

LH.

Connector & terminal

(E159) No. 15 — (E37) No. 2:

Is the resistance less than 1 Ω? Go to step 68. Repair the open

circuit in harness

between ECM con-

nector and intake

oil control solenoid

LH connector.

68 CHECK HARNESS BETWEEN ECM AND IN-

TAKE OIL CONTROL SOLENOID LH CON-

NECTOR.

Measure the resistance between intake oil con-

trol solenoid LH connector and engine ground.

Connector & terminal

(E37) No. 2 — Engine ground:

Is the resistance 1 M

Ω or

more?

Go to step 69. Repair the short

circuit to ground in

harness between

ECM connector

and intake oil con-

trol solenoid LH

connector.

Step Check Yes No

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EN(w/o STI)(diag)-379

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

69 CHECK INTAKE OIL CONTROL SOLENOID

LH.

Check the intake oil control solenoid LH. <Ref.

to FU(w/o STI)-110, INSPECTION, Oil Control

Solenoid.>

Is the intake oil control solenoid

LH normal?

Replace the intake

cam sprocket LH.

<Ref. to ME(w/o

STI)-141, Cam

Sprocket.>

Replace the intake

oil control solenoid

LH. <Ref. to FU(w/

o STI)-108, Oil

Control Solenoid.>

70 CHECK POWER SUPPLY TO THE EXHAUST

OIL CONTROL SOLENOID RH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the exhaust

oil control solenoid RH.

3) Turn the ignition switch to ON.

4) Measure the voltage between exhaust oil

control solenoid RH connector and engine

ground.

Connector & terminal

(E63) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 71. Repair the power

supply circuit.

71 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID RH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and exhaust oil control solenoid

RH.

Connector & terminal

(E159) No. 23 — (E63) No. 2:

Is the resistance less than 1 Ω? Go to step 72. Repair the open

circuit in harness

between ECM con-

nector and exhaust

oil control solenoid

RH connector.

72 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID RH CON-

NECTOR.

Measure the resistance between exhaust oil

control solenoid RH connector and engine

ground.

Connector & terminal

(E63) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 73. Repair the short

circuit to ground in

harness between

ECM connector

and exhaust oil

control solenoid

RH connector.

73 CHECK EXHAUST OIL CONTROL SOLE-

NOID RH.

Check the exhaust oil control solenoid RH.

<Ref. to FU(w/o STI)-110, INSPECTION, Oil

Control Solenoid.>

Is the exhaust oil control sole-

noid RH normal?

Replace the

exhaust cam

sprocket RH. <Ref.

to ME(w/o STI)-

141, Cam

Sprocket.>

Replace the

exhaust oil control

solenoid RH. <Ref.

to FU(w/o STI)-

108, Oil Control

Solenoid.>

74 CHECK POWER SUPPLY TO THE EXHAUST

OIL CONTROL SOLENOID LH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the exhaust

oil control solenoid LH.

3) Turn the ignition switch to ON.

4) Measure the voltage between exhaust oil

control solenoid LH connector and engine

ground.

Connector & terminal

(E66) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 75. Repair the power

supply circuit.

Step Check Yes No

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EN(w/o STI)(diag)-380

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

75 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID LH CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and exhaust oil control solenoid

LH.

Connector & terminal

(E159) No. 31 — (E66) No. 2:

Is the resistance less than 1 Ω? Go to step 76. Repair the open

circuit in harness

between ECM con-

nector and exhaust

oil control solenoid

LH connector.

76 CHECK HARNESS BETWEEN ECM AND EX-

HAUST OIL CONTROL SOLENOID LH CON-

NECTOR.

Measure the resistance between exhaust oil

control solenoid LH connector and engine

ground.

Connector & terminal

(E66) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 77. Repair the short

circuit to ground in

harness between

ECM connector

and exhaust oil

control solenoid

LH connector.

77 CHECK EXHAUST OIL CONTROL SOLE-

NOID LH.

Check the exhaust oil control solenoid LH.

<Ref. to FU(w/o STI)-110, INSPECTION, Oil

Control Solenoid.>

Is the exhaust oil control sole-

noid LH normal?

Replace the

exhaust cam

sprocket LH. <Ref.

to ME(w/o STI)-

141, Cam

Sprocket.>

Replace the

exhaust oil control

solenoid LH. <Ref.

to FU(w/o STI)-

108, Oil Control

Solenoid.>

78 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the mass air flow and intake air temperature

sensor.

3) Measure the resistance of harness between

ECM connector and the mass air flow and

intake air temperature sensor connector.

Connector & terminal

(B134) No. 16 — (B3) No. 3:

(B134) No. 28 — (B3) No. 2:

Is the resistance less than 1 Ω? Go to step 79. Repair the open

circuit of harness

between ECM con-

nector and the

mass air flow and

intake air tempera-

ture sensor con-

nector.

79 CHECK HARNESS BETWEEN ECM AND

MASS AIR FLOW AND INTAKE AIR TEM-

PERATURE SENSOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(B134) No. 16 — Engine ground:

(B134) No. 28 — Engine ground:

Is the resistance 1 MΩ or

more?

Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.> If

the fault occurs

after servicing,

continue the diag-

nosis. Go to step

112.

Repair the ground

short circuit of har-

ness between

ECM connector

and the mass air

flow and intake air

temperature sen-

sor connector.

Step Check Yes No

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EN(w/o STI)(diag)-381

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

80 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

Check the engine coolant temperature sensor.

<Ref. to FU(w/o STI)-94, INSPECTION, Engine

Coolant Temperature Sensor.>

Is the engine coolant tempera-

ture sensor normal?

Go to step 81. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.> If the

fault occurs after

servicing, replace

the ECM. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).> If

the fault still occurs

after replacing the

ECM, continue the

diagnosis. Go to

step 123.

81 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

engine coolant temperature sensor.

3) Measure the resistance of harness between

ECM connector and engine coolant tempera-

ture sensor connector.

Connector & terminal

(E159) No. 27 — (E8) No. 1:

(E158) No. 38 — (E8) No. 2:

Is the resistance less than 1 Ω? Go to step 82. Repair the open

circuit of the har-

ness between the

ECM connector

and engine coolant

temperature sen-

sor connector. If

the fault occurs

after servicing,

replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).> If the fault

still occurs after

replacing the ECM,

continue the diag-

nosis. Go to step

123.

82 CHECK HARNESS BETWEEN ECM AND EN-

GINE COOLANT TEMPERATURE SENSOR

CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 38 — Engine ground:

(E159) No. 27 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 83. Repair the short

circuit to ground in

harness between

ECM connector

and engine coolant

temperature sen-

sor connector. If

the fault occurs

after servicing,

replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).> If the fault

still occurs after

replacing the ECM,

continue the diag-

nosis. Go to step

123.

Step Check Yes No

15WRX_STI_US_EN.book 381 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-382

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

83 CHECK CURRENT DATA.

1) Turn the ignition switch to ON. (engine OFF)

2) Read the values of «Long term fuel trim B1»

and «Atmosphere Pressure», using the Subaru

Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Is the value of «Long term fuel

trim B1» –25 — 25%, and

«Atmosphere Pressure» 80

kPa (600 mmHg, 23.6 inHg) or

more?

Go to step 86. Go to step 84.

84 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Perform the Clear Memory Mode. <Ref. to

EN(w/o STI)(diag)-61, Clear Memory Mode.>

2) Start the engine.

Does the engine start? Go to step 85. Go to step 86.

85 CHECK IDLE SPEED.

Check the idle speed.

Is the idle speed stable? Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.> If

the fault occurs

after servicing,

replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).> If the fault

still occurs after

replacing the ECM,

continue the diag-

nosis. Go to step

123.

Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.> If

the fault occurs

after servicing,

replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).> If the fault

still occurs after

replacing the ECM,

continue the diag-

nosis. Go to step

123.

86 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 340 —

400 kPa (3.5 — 4.1 kgf/cm

, 49

— 58 psi)?

Go to step 87. Go to step 93.

87 CHECK FREEZE FRAME DATA.

Using the Subaru Select Monitor, read the val-

ues in «Fuel Rail Pressure A» and «Com-

manded Fuel Rail Pressure A».

NOTE:

For detailed operation procedures, refer to “En-

gine Freeze Frame Data Display”. <Ref. to

EN(w/o STI)(diag)-43, DISPLAY OF ENGINE

FREEZE FRAME DATA, OPERATION, Subaru

Select Monitor.>

Is the value in «Fuel Rail Pres-

sure A» synchronized with the

one in «Commanded Fuel Rail

Pressure A» in all freeze frame

data?

Go to step 88. Check the high-

pressure fuel

pump. <Ref. to

FU(w/o STI)-82,

INSPECTION,

High Pressure

Fuel Pump.>

Step Check Yes No

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EN(w/o STI)(diag)-383

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

88 CHECK SPARK PLUG.

Check the spark plug. <Ref. to IG(w/o STI)-8,

INSPECTION, Spark Plug.>

Are all spark plug in all cylin-

ders normal?

Go to step 89. • When spark

plugs in some cyl-

inders are faulty:

Replace the faulty

spark plugs of the

cylinders, then

check the ignition

system and fuel

system in the faulty

cylinders. <Ref. to

IG(w/o STI)-4,

Spark Plug.> If the

fault occurs after

servicing, con-

tinue the diagno-

sis. Go to step 123.

• When all spark

plugs in all cylin-

ders are faulty:

Replace faulty

spark plugs in all

cylinders. <Ref. to

IG(w/o STI)-4,

Spark Plug.> If the

fault occurs after

servicing, con-

tinue the diagno-

sis. Go to step 123.

89 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Check for the condition of fault occurrence.

Does the fault occur only within

approx. 15 to 120 minutes after

the engine is stopped?

Go to step 91. • When the fault

occurs in two or

three minutes or a

long time after the

engine is stopped:

Go to step 90.

• When the fault

occurrence pat-

tern is inconsis-

tent: Go to step

123.

90 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

Measure the fuel pressure five minutes after the

engine is stopped. <Ref. to ME(w/o STI)-31,

INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

NOTE:

If the engine does not start, measure the fuel

pressure five minutes after cranking is complet-

ed.

Is the measured value 147 kPa

(1.5 kgf/cm

, 21 psi) or more?

Go to step 123. Replace the pres-

sure regulator.

<Ref. to FU(w/o

STI)-183, Fuel Fil-

ter.>

Step Check Yes No

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EN(w/o STI)(diag)-384

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

91 CHECK PURGE CONTROL SOLENOID

VALVE.

Check purge control solenoid valve 1 and purge

control solenoid valve 2. <Ref. to EC(w/o STI)-

29, INSPECTION, Purge Control Solenoid

Valve.>

Are the purge control solenoid

valve 1 and the purge control

solenoid valve 2 normal?

Go to step 92. Replace the faulty

purge control sole-

noid valve. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

92 CHECK FUEL INJECTOR.

1) After the engine is stopped, scavenge inside

of the intake manifold by applying compressed

air.

2) Measure the HC concentration inside the

intake manifold 15 minutes after scavenging is

completed.

Is the HC concentration less

than 4,000 ppm?

Go to step 123. Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

93 CHECK OF FUEL PUMP.

Check fuel pump. <Ref. to FU(w/o STI)-172,

INSPECTION, Fuel Pump.>

Is the fuel pump normal? Check fuel pump

system. <Ref. to

EN(w/o STI)(diag)-

209, DTC P0230

FUEL PUMP PRI-

MARY CIRCUIT,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).> If the fault

occurs after servic-

ing, continue the

diagnosis. Go to

step 123.

Replace the fuel

pump. <Ref. to

FU(w/o STI)-168,

Fuel Pump.>

94 CHECK FUEL INJECTOR.

Check fuel injector. <Ref. to FU(w/o STI)-70,

INSPECTION, Fuel Injector.>

Are fuel injectors OK? Go to step 95. Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

95 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

fuel injectors.

3) Measure the resistance of harness between

ECM connector and fuel injector connector.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 96. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

96 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

#1 (E158) No. 12 — Engine ground:

#1 (E158) No. 11 — Engine ground:

#2 (E158) No. 24 — Engine ground:

#2 (E158) No. 23 — Engine ground:

#3 (E158) No. 36 — Engine ground:

#3 (E158) No. 35 — Engine ground:

#4 (E158) No. 48 — Engine ground:

#4 (E158) No. 47 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 97. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

Step Check Yes No

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EN(w/o STI)(diag)-385

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

97 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the crankshaft position sensor.

<Ref. to FU(w/o STI)-98, Crankshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Go to step 98.

98 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the camshaft position sensor.

<Ref. to FU(w/o STI)-103, Camshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

99 CHECK INSTALLATION CONDITION OF

CRANKSHAFT POSITION SENSOR.

Is the crankshaft position sen-

sor installed correctly?

Go to step 100. Install the crank-

shaft position sen-

sor correctly. <Ref.

to FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

100 CHECK INSTALLATION CONDITION OF

CAMSHAFT POSITION SENSOR.

Is the camshaft position sensor

installed correctly?

Go to step 101. Install the cam-

shaft position sen-

sor correctly. <Ref.

to FU(w/o STI)-

104, INSTALLA-

TION, Camshaft

Position Sensor.>

101 CHECK POWER SUPPLY TO CRANKSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the crank-

shaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 102. Repair the power

supply circuit.

102 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and crankshaft position sensor

connector.

Connector & terminal

(E158) No. 19 — (E10) No. 2:

(E158) No. 31 — (E10) No. 3:

Is the resistance less than 1 Ω? Go to step 103. Repair the open

circuit in the har-

ness between the

ECM connector

and crankshaft

position sensor

connector.

103 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

Measure the resistance between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 2 — Engine ground:

(E10) No. 3 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 104. Repair short cir-

cuit to ground in

harness between

ECM connector

and crankshaft

position sensor

connector.

Step Check Yes No

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EN(w/o STI)(diag)-386

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

104 CHECK POWER SUPPLY OF INTAKE CAM-

SHAFT POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the intake

camshaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between intake cam-

shaft position sensor connector and engine

ground.

Connector & terminal

(E35) No. 1 (+) — Engine ground (–):

(E36) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 105. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in harness

between main re-

lay connector and

intake camshaft

position sensor

connector

• Poor contact of

coupling connector

105 CHECK HARNESS BETWEEN ECM AND IN-

TAKE CAMSHAFT POSITION SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and intake camshaft position sensor

connector.

Connector & terminal

(E158) No. 21 — (E35) No. 2:

(E158) No. 34 — (E35) No. 3:

(E158) No. 20 — (E36) No. 2:

(E158) No. 34 — (E36) No. 3:

Is the resistance less than 1 Ω? Go to step 106. Repair the open

circuit in the har-

ness between

ECM connector

and intake cam-

shaft position sen-

sor connector.

106 CHECK HARNESS BETWEEN ECM AND IN-

TAKE CAMSHAFT POSITION SENSOR CON-

NECTOR.

Measure the resistance between intake cam-

shaft position sensor connector and engine

ground.

Connector & terminal

(E35) No. 2 — Engine ground:

(E36) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 107. Repair short cir-

cuit to ground in

the harness

between ECM con-

nector and intake

camshaft position

sensor connector.

107 CHECK POWER SUPPLY OF EXHAUST

CAMSHAFT POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the exhaust

camshaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between exhaust cam-

shaft position sensor connector and engine

ground.

Connector & terminal

(E62) No. 1 (+) — Engine ground (–):

(E65) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 108. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

main relay and ex-

haust camshaft po-

sition sensor

connector

• Poor contact of

coupling connector

Step Check Yes No

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EN(w/o STI)(diag)-387

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

108 CHECK HARNESS BETWEEN ECM AND EX-

HAUST CAMSHAFT POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and exhaust crankshaft position sensor

connector.

Connector & terminal

(E158) No. 32 — (E62) No. 2:

(E158) No. 34 — (E62) No. 3:

(E158) No. 33 — (E65) No. 2:

(E158) No. 34 — (E65) No. 3:

Is the resistance less than 1 Ω? Go to step 109. Repair the open

circuit in the har-

ness between

ECM connector

and exhaust cam-

shaft position sen-

sor connector.

109 CHECK HARNESS BETWEEN ECM AND EX-

HAUST CAMSHAFT POSITION SENSOR.

Measure the resistance between exhaust cam-

shaft position sensor connector and engine

ground.

Connector & terminal

(E62) No. 2 — Engine ground:

(E65) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 110. Repair short cir-

cuit to ground in

the harness

between ECM con-

nector and exhaust

camshaft position

sensor connector.

110 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the crankshaft position sensor.

<Ref. to FU(w/o STI)-98, Crankshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Go to step 111.

111 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the camshaft position sensor.

<Ref. to FU(w/o STI)-103, Camshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

112 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

Check the engine coolant temperature sensor.

<Ref. to FU(w/o STI)-94, INSPECTION, Engine

Coolant Temperature Sensor.>

Is the engine coolant tempera-

ture sensor normal?

Go to step 113. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

113 CHECK FUEL PRESSURE.

1) Read the value of «Fuel Rail Pressure A»

during cranking using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

2) Measure the fuel pressure five minutes after

the engine is stopped. <Ref. to ME(w/o STI)-31,

INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the value of «Fuel Rail Pres-

sure A» during cranking 304 —

353 kPa (3.1 — 3.6 kgf/cm

, 44

— 51 psi), and is the fuel pres-

sure five minutes after engine

stop 147 kPa (1.5 kgf/cm

, 21

psi) or more?

Go to step 114. Go to step 122.

Step Check Yes No

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EN(w/o STI)(diag)-388

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

114 CHECK CURRENT DATA.

1) Turn the ignition switch to ON. (engine OFF)

2) Read the value of «Long term fuel trim B1»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Does the value of «Long term

fuel trim B1» fall within a range

of –15 — 15%?

Go to step 115. Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

115 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Start the engine and check the idling speed.

Is the idling speed stable all

time?

It is possible that

the fault comes

from fuel. Replace

fuel.

Go to step 116.

116 CHECK INSTALLATION CONDITION OF

CRANKSHAFT POSITION SENSOR.

Is the crankshaft position sen-

sor installed correctly?

Go to step 117. Install the crank-

shaft position sen-

sor correctly. <Ref.

to FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

117 CHECK POWER SUPPLY TO CRANKSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the crank-

shaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 118. Repair the power

supply circuit.

118 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and crankshaft position sensor

connector.

Connector & terminal

(E158) No. 19 — (E10) No. 2:

(E158) No. 31 — (E10) No. 3:

Is the resistance less than 1 Ω? Go to step 119. Repair the open

circuit in the har-

ness between the

ECM connector

and crankshaft

position sensor

connector.

119 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

Measure the resistance between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 2 — Engine ground:

(E10) No. 3 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 120. Repair short cir-

cuit to ground in

harness between

ECM connector

and crankshaft

position sensor

connector.

120 CHECK COMPRESSION PRESSURE.

Check the compression pressure. <Ref. to

ME(w/o STI)-23, INSPECTION, Compres-

sion.>

Is the compression pressure

normal?

Go to step 121. Check the engine.

<Ref. to ME(w/o

STI)-352,

INSPECTION,

Engine Trouble in

General.>

Step Check Yes No

15WRX_STI_US_EN.book 388 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-389

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

121 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the crankshaft position sensor.

<Ref. to FU(w/o STI)-98, Crankshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Check the valve

timing. <Ref. to

ME(w/o STI)-116,

Timing Chain

Assembly.> When

the valve timing is

normal, replace

the ECM. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

122 CHECK OF FUEL PUMP.

Check fuel pump. <Ref. to FU(w/o STI)-172,

INSPECTION, Fuel Pump.>

Is the fuel pump normal? Check fuel pump

system. <Ref. to

EN(w/o STI)(diag)-

209, DTC P0230

FUEL PUMP PRI-

MARY CIRCUIT,

Diagnostic Proce-

dure with Diagnos-

tic Trouble Code

(DTC).>

Replace the fuel

pump. <Ref. to

FU(w/o STI)-168,

Fuel Pump.>

123 CHECK FUEL PRESSURE.

1) Read the value of «Fuel Rail Pressure A»

during cranking using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

2) Measure the fuel pressure five minutes after

the engine is stopped. <Ref. to ME(w/o STI)-31,

INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the value of «Fuel Rail Pres-

sure A» during cranking 304 —

353 kPa (3.1 — 3.6 kgf/cm

, 44

— 51 psi), and is the fuel pres-

sure five minutes after engine

stop 147 kPa (1.5 kgf/cm

, 21

psi) or more?

Go to step 124. Go to step 131.

124 CHECK CURRENT DATA.

1) Turn the ignition switch to ON. (engine OFF)

2) Read the value of «Long term fuel trim B1»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, DISPLAY CURRENT

ENGINE DATA, OPERATION, Subaru Select

Monitor.>

Does the value of «Long term

fuel trim B1» fall within a range

of –15 — 15%?

Go to step 125. Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

125 CHECK FOR MALFUNCTION OCCUR-

RENCE.

Start the engine and check the idling speed.

Is the idling speed stable all

time?

It is possible that

the fault comes

from fuel. Replace

fuel.

Go to step 126.

Step Check Yes No

15WRX_STI_US_EN.book 389 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-390

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

126 CHECK INSTALLATION CONDITION OF

CRANKSHAFT POSITION SENSOR.

Is the crankshaft position sen-

sor installed correctly?

Go to step 127. Install the crank-

shaft position sen-

sor correctly. <Ref.

to FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

127 CHECK POWER SUPPLY TO CRANKSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the crank-

shaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 128. Repair the power

supply circuit.

128 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and crankshaft position sensor

connector.

Connector & terminal

(E158) No. 19 — (E10) No. 2:

(E158) No. 31 — (E10) No. 3:

Is the resistance less than 1 Ω? Go to step 129. Repair the open

circuit in the har-

ness between the

ECM connector

and crankshaft

position sensor

connector.

129 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

Measure the resistance between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 2 — Engine ground:

(E10) No. 3 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 130. Repair short cir-

cuit to ground in

harness between

ECM connector

and crankshaft

position sensor

connector.

130 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the crankshaft position sensor.

<Ref. to FU(w/o STI)-98, Crankshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

131 CHECK OF FUEL PUMP.

Check fuel pump. <Ref. to FU(w/o STI)-172,

INSPECTION, Fuel Pump.>

Is the fuel pump normal? Go to step 132. Replace the fuel

pump. <Ref. to

FU(w/o STI)-168,

Fuel Pump.>

132 CHECK FUEL PUMP SYSTEM.

Check fuel pump system. <Ref. to EN(w/o

STI)(diag)-209, DTC P0230 FUEL PUMP PRI-

MARY CIRCUIT, Diagnostic Procedure with

Diagnostic Trouble Code (DTC).>

Is the fuel pump system nor-

mal?

Go to step 133. Repair the fuel

pump system.

<Ref. to EN(w/o

STI)(diag)-209,

DTC P0230 FUEL

PUMP PRIMARY

CIRCUIT, Diag-

nostic Procedure

with Diagnostic

Trouble Code

(DTC).>

Step Check Yes No

15WRX_STI_US_EN.book 390 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-391

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

133 CHECK PURGE CONTROL SOLENOID

VALVE.

Check purge control solenoid valve 1 and purge

control solenoid valve 2. <Ref. to EC(w/o STI)-

29, INSPECTION, Purge Control Solenoid

Valve.>

Are the purge control solenoid

valve 1 and the purge control

solenoid valve 2 normal?

Go to step 134. Replace the faulty

purge control sole-

noid valve. <Ref. to

EC(w/o STI)-22,

Purge Control

Solenoid Valve.>

134 CHECK FUEL INJECTOR.

1) After the engine is stopped, scavenge inside

of the intake manifold by applying compressed

air.

2) Measure the HC concentration inside the

intake manifold 15 minutes after scavenging is

completed.

Is the HC concentration less

than 4,000 ppm?

Go to step 135. Replace the fuel

injector. <Ref. to

FU(w/o STI)-51,

Fuel Injector.>

135 CHECK INTAKE VALVE.

Check the intake valve. <Ref. to ME(w/o STI)-

236, INSPECTION, Cylinder Head.>

Is there any deposit in the

intake valve?

Clean the intake

valve. <Ref. to

ME(w/o STI)-215,

Cylinder Head.>

Go to step 136.

136 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

Check the engine coolant temperature sensor.

<Ref. to FU(w/o STI)-94, INSPECTION, Engine

Coolant Temperature Sensor.>

Is the engine coolant tempera-

ture sensor normal?

Go to step 137. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

137 CHECK INSTALLATION CONDITION OF

CRANKSHAFT POSITION SENSOR.

Is the crankshaft position sen-

sor installed correctly?

Go to step 138. Install the crank-

shaft position sen-

sor correctly. <Ref.

to FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

138 CHECK INSTALLATION CONDITION OF

CAMSHAFT POSITION SENSOR.

Is the camshaft position sensor

installed correctly?

Go to step 139. Install the cam-

shaft position sen-

sor correctly. <Ref.

to FU(w/o STI)-

104, INSTALLA-

TION, Camshaft

Position Sensor.>

139 CHECK POWER SUPPLY TO CRANKSHAFT

POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the crank-

shaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 140. Repair the power

supply circuit.

140 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and crankshaft position sensor

connector.

Connector & terminal

(E158) No. 19 — (E10) No. 2:

(E158) No. 31 — (E10) No. 3:

Is the resistance less than 1 Ω? Go to step 141. Repair the open

circuit in the har-

ness between the

ECM connector

and crankshaft

position sensor

connector.

Step Check Yes No

15WRX_STI_US_EN.book 391 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-392

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

141 CHECK HARNESS BETWEEN ECM AND

CRANKSHAFT POSITION SENSOR CON-

NECTOR.

Measure the resistance between crankshaft

position sensor connector and engine ground.

Connector & terminal

(E10) No. 2 — Engine ground:

(E10) No. 3 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 142. Repair short cir-

cuit to ground in

harness between

ECM connector

and crankshaft

position sensor

connector.

142 CHECK POWER SUPPLY OF INTAKE CAM-

SHAFT POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the intake

camshaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between intake cam-

shaft position sensor connector and engine

ground.

Connector & terminal

(E35) No. 1 (+) — Engine ground (–):

(E36) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 143. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit or

short circuit to

ground in harness

between main re-

lay connector and

intake camshaft

position sensor

connector

• Poor contact of

coupling connector

143 CHECK HARNESS BETWEEN ECM AND IN-

TAKE CAMSHAFT POSITION SENSOR CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and intake camshaft position sensor

connector.

Connector & terminal

(E158) No. 21 — (E35) No. 2:

(E158) No. 34 — (E35) No. 3:

(E158) No. 20 — (E36) No. 2:

(E158) No. 34 — (E36) No. 3:

Is the resistance less than 1 Ω? Go to step 144. Repair the open

circuit in the har-

ness between

ECM connector

and intake cam-

shaft position sen-

sor connector.

144 CHECK HARNESS BETWEEN ECM AND IN-

TAKE CAMSHAFT POSITION SENSOR CON-

NECTOR.

Measure the resistance between intake cam-

shaft position sensor connector and engine

ground.

Connector & terminal

(E35) No. 2 — Engine ground:

(E36) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 145. Repair short cir-

cuit to ground in

the harness

between ECM con-

nector and intake

camshaft position

sensor connector.

145 CHECK POWER SUPPLY OF EXHAUST

CAMSHAFT POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the exhaust

camshaft position sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between exhaust cam-

shaft position sensor connector and engine

ground.

Connector & terminal

(E62) No. 1 (+) — Engine ground (–):

(E65) No. 1 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 146. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

main relay and ex-

haust camshaft po-

sition sensor

connector

• Poor contact of

coupling connector

Step Check Yes No

15WRX_STI_US_EN.book 392 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-393

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

146 CHECK HARNESS BETWEEN ECM AND EX-

HAUST CAMSHAFT POSITION SENSOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and exhaust crankshaft position sensor

connector.

Connector & terminal

(E158) No. 32 — (E62) No. 2:

(E158) No. 34 — (E62) No. 3:

(E158) No. 33 — (E65) No. 2:

(E158) No. 34 — (E65) No. 3:

Is the resistance less than 1 Ω? Go to step 147. Repair the open

circuit in the har-

ness between

ECM connector

and exhaust cam-

shaft position sen-

sor connector.

147 CHECK HARNESS BETWEEN ECM AND EX-

HAUST CAMSHAFT POSITION SENSOR.

Measure the resistance between exhaust cam-

shaft position sensor connector and engine

ground.

Connector & terminal

(E62) No. 2 — Engine ground:

(E65) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 148. Repair short cir-

cuit to ground in

the harness

between ECM con-

nector and exhaust

camshaft position

sensor connector.

148 CHECK COMPRESSION PRESSURE.

Check the compression pressure. <Ref. to

ME(w/o STI)-23, INSPECTION, Compres-

sion.>

Is the compression pressure

normal?

Go to step 149. Check the engine.

<Ref. to ME(w/o

STI)-352,

INSPECTION,

Engine Trouble in

General.>

149 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the crankshaft position sensor.

<Ref. to FU(w/o STI)-98, Crankshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Go to step 150.

150 CHECK FOR MALFUNCTION OCCUR-

RENCE.

1) Replace the camshaft position sensor.

<Ref. to FU(w/o STI)-103, Camshaft Position

Sensor.>

2) Check that the fault is removed.

Is the fault removed? Perform the Clear

Memory Mode to

complete. <Ref. to

EN(w/o STI)(diag)-

61, Clear Memory

Mode.>

Check the valve

timing. <Ref. to

ME(w/o STI)-116,

Timing Chain

Assembly.> When

the valve timing is

normal, replace

the ECM. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

Step Check Yes No

15WRX_STI_US_EN.book 393 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-394

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

EZ:DTC P1C00 BATTERY MONITOR MODULE "A"

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-182, DTC P1C00 BATTERY MONITOR MODULE "A",

Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK DTC.

Check for DTC. <Ref. to EN(w/o STI)(diag)-46,

Read Diagnostic Trouble Code (DTC).>

Is P1C00 displayed in «Present

fault»?

Replace the bat-

tery sensor. <Ref.

to SC(w/o STI)-56,

Battery Sensor.>

Even if DTC is

detected, it has

returned to a nor-

mal condition at

this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

15WRX_STI_US_EN.book 394 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-395

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FA:DTC P2004 INTAKE MANIFOLD RUNNER CONTROL STUCK OPEN (BANK 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-183, DTC P2004 INTAKE MANIFOLD RUNNER CON-

TROL STUCK OPEN (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK TUMBLE GENERATOR VALVE RH.

1) Remove the tumble generator valve assem-

bly RH.

2) Check the tumble generator valve.

Is there any dirt or clogging with

foreign objects in the tumble

generator valve?

Clean the tumble

generator valve.

Replace the tum-

ble generator valve

RH. <Ref. to FU(w/

o STI)-43, Tumble

Generator Valve

Assembly.>

15WRX_STI_US_EN.book 395 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-396

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FB:DTC P2005 INTAKE MANIFOLD RUNNER CONTROL STUCK OPEN (BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-184, DTC P2005 INTAKE MANIFOLD RUNNER CON-

TROL STUCK OPEN (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK TUMBLE GENERATOR VALVE LH.

1) Remove the tumble generator valve assem-

bly LH.

2) Check the tumble generator valve.

Is there any dirt or clogging with

foreign objects in the tumble

generator valve?

Clean the tumble

generator valve.

Replace the tum-

ble generator valve

LH. <Ref. to FU(w/

o STI)-43, Tumble

Generator Valve

Assembly.>

15WRX_STI_US_EN.book 396 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-397

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FC:DTC P2006 INTAKE MANIFOLD RUNNER CONTROL STUCK CLOSED

(BANK 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-185, DTC P2006 INTAKE MANIFOLD RUNNER CON-

TROL STUCK CLOSED (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK TUMBLE GENERATOR VALVE RH.

1) Remove the tumble generator valve assem-

bly RH.

2) Check the tumble generator valve.

Is there any dirt or clogging with

foreign objects in the tumble

generator valve?

Clean the tumble

generator valve.

Replace the tum-

ble generator valve

RH. <Ref. to FU(w/

o STI)-43, Tumble

Generator Valve

Assembly.>

15WRX_STI_US_EN.book 397 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-398

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FD:DTC P2007 INTAKE MANIFOLD RUNNER CONTROL STUCK CLOSED

(BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-186, DTC P2007 INTAKE MANIFOLD RUNNER CON-

TROL STUCK CLOSED (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK TUMBLE GENERATOR VALVE LH.

1) Remove the tumble generator valve assem-

bly LH.

2) Check the tumble generator valve.

Is there any dirt or clogging with

foreign objects in the tumble

generator valve?

Clean the tumble

generator valve.

Replace the tum-

ble generator valve

LH. <Ref. to FU(w/

o STI)-43, Tumble

Generator Valve

Assembly.>

15WRX_STI_US_EN.book 398 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-399

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FE:DTC P2009 INTAKE MANIFOLD RUNNER CONTROL CIRCUIT LOW (BANK 1)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-187, DTC P2009 INTAKE MANIFOLD RUNNER CON-

TROL CIRCUIT LOW (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

RH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 14 (+) — Engine ground (–):

(E159) No. 30 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

harness between

ECM connector

and tumble gener-

ator valve actuator

RH connector.

Replace the tum-

ble generator valve

actuator RH. <Ref.

to FU(w/o STI)-45,

Tumble Generator

Valve Actuator.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E51

E55

213

E55

1B40

EN-10339

2C27

3C19

4C14

5C30

E51

1B41

4C22

5C6

E158B:

E159C:

ECM

TUMBLE GENERATOR

VALVE ACTUATOR LH

TUMBLE GENERATOR

VALVE ACTUATOR RH

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 399 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-400

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FF:DTC P2012 INTAKE MANIFOLD RUNNER CONTROL CIRCUIT LOW (BANK 2)

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-188, DTC P2012 INTAKE MANIFOLD RUNNER CON-

TROL CIRCUIT LOW (BANK 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

LH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(E159) No. 6 (+) — Engine ground (–):

(E159) No. 22 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

harness between

ECM connector

and tumble gener-

ator valve actuator

LH connector.

Replace the tum-

ble generator valve

actuator LH. <Ref.

to FU(w/o STI)-45,

Tumble Generator

Valve Actuator.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E51

E55

213

E55

1B40

EN-10339

2C27

3C19

4C14

5C30

E51

1B41

4C22

5C6

E158B:

E159C:

ECM

TUMBLE GENERATOR

VALVE ACTUATOR LH

TUMBLE GENERATOR

VALVE ACTUATOR RH

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 400 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-401

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FG:DTC P2016 TUMBLE GENERATED VALVE POSITION SENSOR 1 CIRCUIT

LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-189, DTC P2016 TUMBLE GENERATED VALVE POSI-

TION SENSOR 1 CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E51

E55

213

E55

1B40

EN-10339

2C27

3C19

4C14

5C30

E51

1B41

4C22

5C6

E158B:

E159C:

ECM

TUMBLE GENERATOR

VALVE ACTUATOR LH

TUMBLE GENERATOR

VALVE ACTUATOR RH

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 401 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-402

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «TGV Position Sensor R»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «TGV Position

Sensor R» less than 0.2 V?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK POWER SUPPLY OF TUMBLE GEN-

ERATOR VALVE ACTUATOR RH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from tumble gen-

erator valve actuator RH.

3) Turn the ignition switch to ON.

4) Measure the voltage between tumble gener-

ator valve actuator RH connector and engine

ground.

Connector & terminal

(E55) No. 3 (+) — Engine ground (–):

Is the voltage 4.5 V or more? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and tumble gener-

ator valve actuator

RH connector

• Poor contact of

ECM connector

3 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

RH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and tumble generator valve

actuator RH connector.

Connector & terminal

(E158) No. 40 — (E55) No. 1:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit in harness

between ECM con-

nector and tumble

generator valve

actuator RH con-

nector.

4 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

RH CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 40 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and tumble gener-

ator valve actuator

RH connector.

5 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and tumble gen-

erator valve actuator RH connector.

Is there poor contact of ECM or

the tumble generator valve

actuator RH connector?

Repair the poor

contact of ECM or

tumble generator

valve actuator RH

connector.

Replace the tum-

ble generator valve

actuator RH. <Ref.

to FU(w/o STI)-43,

Tumble Generator

Valve Assembly.>

15WRX_STI_US_EN.book 402 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-403

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FH:DTC P2017 TUMBLE GENERATED VALVE POSITION SENSOR 1 CIRCUIT

HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-190, DTC P2017 TUMBLE GENERATED VALVE POSI-

TION SENSOR 1 CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E51

E55

213

E55

1B40

EN-10339

2C27

3C19

4C14

5C30

E51

1B41

4C22

5C6

E158B:

E159C:

ECM

TUMBLE GENERATOR

VALVE ACTUATOR LH

TUMBLE GENERATOR

VALVE ACTUATOR RH

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 403 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-404

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «TGV Position Sensor R»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «TGV Position

Sensor R» 5 V or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

RH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from tumble gen-

erator valve actuator RH.

3) Start the engine.

4) Read the value of «TGV Position Sensor R»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «TGV Position

Sensor R» 5 V or more?

Repair the short

circuit to power in

harness between

ECM connector

and tumble gener-

ator valve actuator

RH connector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

RH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Measure the resistance of harness between

tumble generator valve actuator RH connector

and engine ground.

Connector & terminal

(E55) No. 2 — Engine ground:

Is the resistance less than 5 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and tumble gener-

ator valve actuator

RH connector

• Poor contact of

ECM connector

4 CHECK FOR POOR CONTACT.

Check for poor contact of tumble generator

valve actuator RH connector.

Is there poor contact of the tum-

ble generator valve actuator RH

connector?

Repair the poor

contact of tumble

generator valve

actuator RH con-

nector.

Replace the tum-

ble generator valve

actuator RH. <Ref.

to FU(w/o STI)-43,

Tumble Generator

Valve Assembly.>

15WRX_STI_US_EN.book 404 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-405

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FI: DTC P2021 TUMBLE GENERATED VALVE POSITION SENSOR 2 CIRCUIT

LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-191, DTC P2021 TUMBLE GENERATED VALVE POSI-

TION SENSOR 2 CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E51

E55

213

E55

1B40

EN-10339

2C27

3C19

4C14

5C30

E51

1B41

4C22

5C6

E158B:

E159C:

ECM

TUMBLE GENERATOR

VALVE ACTUATOR LH

TUMBLE GENERATOR

VALVE ACTUATOR RH

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 405 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-406

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «TGV Position Sensor L»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «TGV Position

Sensor L» less than 0.2 V?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK POWER SUPPLY OF TUMBLE GEN-

ERATOR VALVE ACTUATOR LH.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from tumble gen-

erator valve actuator LH.

3) Turn the ignition switch to ON.

4) Measure the voltage between tumble gener-

ator valve actuator LH connector and engine

ground.

Connector & terminal

(E51) No. 3 (+) — Engine ground (–):

Is the voltage 4.5 V or more? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and tumble gener-

ator valve actuator

LH connector

• Poor contact of

ECM connector

3 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

LH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and tumble generator valve

actuator LH connector.

Connector & terminal

(E158) No. 41 — (E51) No. 1:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit in harness

between ECM con-

nector and tumble

generator valve

actuator LH con-

nector.

4 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

LH CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 41 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and tumble gener-

ator valve actuator

LH connector.

5 CHECK FOR POOR CONTACT.

Check for poor contact of ECM and tumble gen-

erator valve actuator LH connector.

Is there poor contact of ECM or

the tumble generator valve

actuator LH connector?

Repair the poor

contact of ECM or

tumble generator

valve actuator LH

connector.

Replace the tum-

ble generator valve

actuator LH. <Ref.

to FU(w/o STI)-43,

Tumble Generator

Valve Assembly.>

15WRX_STI_US_EN.book 406 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-407

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FJ:DTC P2022 TUMBLE GENERATED VALVE POSITION SENSOR 2 CIRCUIT

HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-192, DTC P2022 TUMBLE GENERATED VALVE POSI-

TION SENSOR 2 CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Engine stalls.

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

E51

E55

213

E55

1B40

EN-10339

2C27

3C19

4C14

5C30

E51

1B41

4C22

5C6

E158B:

E159C:

ECM

TUMBLE GENERATOR

VALVE ACTUATOR LH

TUMBLE GENERATOR

VALVE ACTUATOR RH

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 407 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-408

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK CURRENT DATA.

1) Start the engine.

2) Read the value of «TGV Position Sensor L»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «TGV Position

Sensor L» 5 V or more?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

2 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

LH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from tumble gen-

erator valve actuator LH.

3) Start the engine.

4) Read the value of «TGV Position Sensor L»

using the Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «TGV Position

Sensor L» 5 V or more?

Repair the short

circuit to power in

harness between

ECM connector

and tumble gener-

ator valve actuator

LH connector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

TUMBLE GENERATOR VALVE ACTUATOR

LH CONNECTOR.

1) Turn the ignition switch to OFF.

2) Measure the resistance of harness between

tumble generator valve actuator LH connector

and engine ground.

Connector & terminal

(E51) No. 2 — Engine ground:

Is the resistance less than 5 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and tumble gener-

ator valve actuator

LH connector

• Poor contact of

ECM connector

4 CHECK FOR POOR CONTACT.

Check for poor contact of tumble generator

valve actuator LH connector.

Is there poor contact of the tum-

ble generator valve actuator LH

connector?

Repair the poor

contact of tumble

generator valve

actuator LH con-

nector.

Replace the tum-

ble generator valve

actuator LH. <Ref.

to FU(w/o STI)-43,

Tumble Generator

Valve Assembly.>

15WRX_STI_US_EN.book 408 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-409

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FK:DTC P2096 POST CATALYST FUEL TRIM SYSTEM TOO LEAN (BANK 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-193, DTC P2096 POST CATALYST FUEL TRIM SYS-

TEM TOO LEAN (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 409 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-410

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 410 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-411

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Go to step 2.

2 CHECK FRONT OXYGEN (A/F) SENSOR

CONNECTOR AND COUPLING CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 3.

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 411 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-412

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

3 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

front oxygen (A/F) sensor.

3) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

Is the resistance less than 1 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector

• Poor contact of

coupling connector

4 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

Measure the resistance between ECM connec-

tor and chassis ground.

Connector & terminal

(B158) No. 15 — Chassis ground:

(B158) No. 27 — Chassis ground:

(B158) No. 39 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector.

5 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between front oxygen

(A/F) sensor connector and chassis ground.

Connector & terminal

(E24) No. 1 (+) — Chassis ground (–):

(E24) No. 4 (+) — Chassis ground (–):

(E24) No. 5 (+) — Chassis ground (–):

Is the voltage 8 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

Go to step 6.

6 CHECK EXHAUST SYSTEM. Are there holes or loose bolts

on exhaust system?

Repair the exhaust

system.

Go to step 7.

7 CHECK AIR INTAKE SYSTEM. Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

Go to step 8.

8 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

1) Connect the front oxygen (A/F) sensor con-

nector.

2) Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 328 —

358 kPa (3.3 — 3.7 kgf/cm

, 48

— 52 psi)?

Go to step 9. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

Step Check Yes No

15WRX_STI_US_EN.book 412 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-413

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

9 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

1) Start the engine and warm up completely.

2) Read the value of «Coolant Temp.» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Coolant Temp.»

75°C (167°F) or more?

Go to step 10. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

10 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Read the value of «Mass Air Flow» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value in «Mass Air

Flow» 2.0 — 5.0 g/s (0.26 —

0.66 lb/s)?

Go to step 11. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 413 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-414

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

11 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Open the front hood.

6) Measure the ambient temperature.

7) Read the value of «IAT Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Subtract ambient temperature

value from the value of «IAT

Sensor #11». Is the obtained

value –10 — 50°C (–18 —

90°F)?

Go to step 12. Check the mass air

flow and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-118, Mass

Air Flow and Intake

Air Temperature

Sensor.>

12 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

keep the engine speed at 3,000 rpm. (2 minutes

maximum)

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.490 V or more?

Go to step 13. Go to step 14.

13 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

rapidly reduce the engine speed from 3,000

rpm.

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.250 V or more?

Go to step 15. Go to step 14.

Step Check Yes No

15WRX_STI_US_EN.book 414 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-415

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

14 CHECK REAR OXYGEN SENSOR CONNEC-

TOR AND COUPLING CONNECTOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 16.

15 CHECK FRONT OXYGEN (A/F) SENSOR US-

ING REAR OXYGEN SENSOR SIGNAL.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), then

keep the engine idling for 5 minutes or more.

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» kept at 0.250 V or less for

5 minutes or more?

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

Go to step 16.

16 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 17. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and rear oxygen

sensor connector

• Poor contact of

coupling connector

17 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between rear oxygen

sensor connector and chassis ground.

Connector & terminal

(E25) No. 4 (+) — Chassis ground (–):

Is the voltage 0.2 — 0.5 V? Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and rear oxygen

sensor connector

• Poor contact of

ECM connector

• Poor contact of

coupling connector

Step Check Yes No

15WRX_STI_US_EN.book 415 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-416

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FL:DTC P2097 POST CATALYST FUEL TRIM SYSTEM TOO RICH (BANK 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-194, DTC P2097 POST CATALYST FUEL TRIM SYS-

TEM TOO RICH (BANK 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 416 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-417

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 417 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-418

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Go to step 2.

2 CHECK FRONT OXYGEN (A/F) SENSOR

CONNECTOR AND COUPLING CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 3.

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 418 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-419

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

3 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

front oxygen (A/F) sensor.

3) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

Is the resistance less than 1 Ω? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector

• Poor contact of

coupling connector

4 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

Measure the resistance between ECM connec-

tor and chassis ground.

Connector & terminal

(E158) No. 15 — Chassis ground:

(E158) No. 27 — Chassis ground:

(E158) No. 39 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector.

5 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between front oxygen

(A/F) sensor connector and chassis ground.

Connector & terminal

(E24) No. 1 (+) — Chassis ground (–):

(E24) No. 4 (+) — Chassis ground (–):

(E24) No. 5 (+) — Chassis ground (–):

Is the voltage 8 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

Go to step 6.

6 CHECK EXHAUST SYSTEM. Are there holes or loose bolts

on exhaust system?

Repair the exhaust

system.

Go to step 7.

7 CHECK AIR INTAKE SYSTEM. Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

Go to step 8.

8 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

1) Connect the front oxygen (A/F) sensor con-

nector.

2) Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 328 —

358 kPa (3.3 — 3.7 kgf/cm

, 48

— 52 psi)?

Go to step 9. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

Step Check Yes No

15WRX_STI_US_EN.book 419 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-420

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

9 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

1) Start the engine and warm up completely.

2) Read the value of «Coolant Temp.» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Coolant Temp.»

75°C (167°F) or more?

Go to step 10. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

10 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Read the value of «Mass Air Flow» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value in «Mass Air

Flow» 2.0 — 5.0 g/s (0.26 —

0.66 lb/s)?

Go to step 11. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 420 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-421

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

11 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Open the front hood.

6) Measure the ambient temperature.

7) Read the value of «IAT Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Subtract ambient temperature

value from the value of «IAT

Sensor #11». Is the obtained

value –10 — 50°C (–18 —

90°F)?

Go to step 12. Check the mass air

flow and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-118, Mass

Air Flow and Intake

Air Temperature

Sensor.>

12 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

keep the engine speed at 3,000 rpm. (2 minutes

maximum)

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.490 V or more?

Go to step 13. Go to step 14.

13 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

rapidly reduce the engine speed from 3,000

rpm.

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.250 V or less?

Go to step 15. Go to step 14.

Step Check Yes No

15WRX_STI_US_EN.book 421 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-422

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

14 CHECK REAR OXYGEN SENSOR CONNEC-

TOR AND COUPLING CONNECTOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 16.

15 CHECK FRONT OXYGEN (A/F) SENSOR US-

ING REAR OXYGEN SENSOR SIGNAL.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), then

keep the engine idling for 5 minutes or more.

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» kept at 0.8 V or more for 5

minutes or more?

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

Go to step 16.

16 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 17. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and rear oxygen

sensor connector

• Poor contact of

coupling connector

17 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between rear oxygen

sensor connector and chassis ground.

Connector & terminal

(E25) No. 4 (+) — Chassis ground (–):

Is the voltage 0.2 — 0.5 V? Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and rear oxygen

sensor connector

• Poor contact of

ECM connector

• Poor contact of

coupling connector

Step Check Yes No

15WRX_STI_US_EN.book 422 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-423

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FM:DTC P2101 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT RANGE/

PERFORMANCE

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-195, DTC P2101 THROTTLE ACTUATOR CONTROL

MOTOR CIRCUIT RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 423 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-424

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK ELECTRONIC THROTTLE CON-

TROL RELAY.

1) Turn the ignition switch to OFF.

2) Remove the electronic throttle control relay.

3) Connect the battery to terminals No. 16 and

No. 17 of electronic throttle control relay.

4) Measure the resistance between electronic

throttle control relay terminals.

Terminals

No. 14 — No. 15:

Is the resistance less than 1 Ω? Go to step 2. Replace the elec-

tronic throttle con-

trol relay. <Ref. to

FU(w/o STI)-139,

Electronic Throttle

Control Relay.>

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 424 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-425

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK POWER SUPPLY OF ELECTRONIC

THROTTLE CONTROL RELAY.

Measure the voltage between electronic throttle

control relay connector and chassis ground.

Connector & terminal

(B225) No. 15 (+) — Chassis ground (–):

Is the voltage 10 V or more? Go to step 3. Repair the open or

ground short circuit

of power supply

circuit.

3 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

1) Disconnect the connector from ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between electronic

throttle control relay connector and chassis

ground.

Connector & terminal

(B225) No. 17 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control relay con-

nector.

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

1) Turn the ignition switch to OFF.

2) Measure the resistance between electronic

throttle control relay connector and chassis

ground.

Connector & terminal

(B225) No. 14 — Chassis ground:

(B225) No. 17 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and electronic

throttle control

relay connector.

5 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

Measure the resistance between ECM connec-

tor and electronic throttle control relay connec-

tor.

Connector & terminal

(B134) No. 39 — (B225) No. 17:

(B134) No. 11 — (B225) No. 14:

Is the resistance less than 1 Ω? Go to step 6. Repair the open

circuit in harness

between ECM con-

nector and elec-

tronic throttle

control relay con-

nector.

6 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from electronic

throttle control.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 18 — Engine ground:

(E158) No. 17 — Engine ground:

(E158) No. 29 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 7. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

7 CHECK SHORT CIRCUIT INSIDE THE ECM.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 1 — Engine ground:

(E57) No. 4 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 8. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

Replace the ECM if

defective. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

Step Check Yes No

15WRX_STI_US_EN.book 425 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-426

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

8 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance of harness between

ECM connector and electronic throttle control

connector.

Connector & terminal

(E158) No. 17 — (E57) No. 1:

(E158) No. 30 — (E57) No. 3:

(E158) No. 29 — (E57) No. 4:

Is the resistance less than 1 Ω? Go to step 9. Repair the open

circuit of harness

between ECM con-

nector and elec-

tronic throttle

control connector.

9 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 3 — Engine ground:

Is the resistance less than 5 Ω? Go to step 10. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

ECM connector

• Poor contact of

coupling connector

10 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 1 (+) — Engine ground (–):

(E57) No. 4 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Go to step 11.

11 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 18 — (E158) No. 17:

(E158) No. 18 — (E158) No. 29:

Is the resistance 1 MΩ or

more?

Go to step 12. Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

12 CHECK SENSOR OUTPUT.

1) Connect all connectors.

2) Start the engine and warm up completely.

3) Stop the engine, and then turn the ignition

switch to ON (engine OFF).

4) Read the value of «Main-Throttle Sensor»

using Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «Main-Throttle

Sensor» 0.60 — 0.65 V?

Go to step 13. Repair the poor

contact of elec-

tronic throttle con-

trol connector.

Replace the elec-

tronic throttle con-

trol if defective.

<Ref. to FU(w/o

STI)-15, Throttle

Body.>

Step Check Yes No

15WRX_STI_US_EN.book 426 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-427

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

13 CHECK SENSOR OUTPUT.

Read the value of «Sub-Throttle Sensor» using

Subaru Select Monitor.

NOTE:

For detailed operation procedures, refer to

“Current Data Display For Engine”. <Ref. to

EN(w/o STI)(diag)-37, Subaru Select Monitor.>

Is the value of «Sub-Throttle

Sensor» 0.60 — 0.65 V?

Go to step 14. Repair the poor

contact of elec-

tronic throttle con-

trol connector.

Replace the elec-

tronic throttle con-

trol if defective.

<Ref. to FU(w/o

STI)-15, Throttle

Body.>

14 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL MO-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

electronic throttle control.

3) Measure the resistance between ECM con-

nector and electronic throttle control connector.

Connector & terminal

(E159) No. 1 — (E57) No. 5:

(E159) No. 2 — (E57) No. 6:

Is the resistance less than 1 Ω? Go to step 15. Repair the open

circuit of harness

between ECM con-

nector and elec-

tronic throttle

control.

15 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL MO-

TOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 5 (+) — Engine ground (–):

(E57) No. 6 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Go to step 16.

16 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL MO-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 5 — Engine ground:

(E57) No. 6 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 17. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

17 CHECK ELECTRONIC THROTTLE CON-

TROL MOTOR HARNESS.

Measure the resistance between electronic

throttle control connectors.

Connector & terminal

(E57) No. 5 — (E57) No. 6:

Is the resistance 1 MΩ or

more?

Go to step 18. Repair the short

circuit in harness

between ECM con-

nector and elec-

tronic throttle

control connector.

18 CHECK ELECTRONIC THROTTLE CON-

TROL GROUND CIRCUIT.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(B134) No. 35 — Engine ground:

(B134) No. 47 — Engine ground:

(E159) No. 10 — Engine ground:

(E159) No. 17 — Engine ground:

(E159) No. 18 — Engine ground:

(E159) No. 25 — Engine ground:

(E159) No. 26 — Engine ground:

Is the resistance less than 5 Ω? Go to step 19. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

coupling connector

Step Check Yes No

15WRX_STI_US_EN.book 427 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-428

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

19 CHECK ELECTRONIC THROTTLE CON-

TROL.

Measure the resistance between electronic

throttle control terminals.

Terminals

No. 5 — No. 6:

Is the resistance 50 Ω or less? Go to step 20. Replace the elec-

tronic throttle con-

trol. <Ref. to FU(w/

o STI)-15, Throttle

Body.>

20 CHECK ELECTRONIC THROTTLE CON-

TROL.

Move the throttle valve to the fully open and fully

closed positions with fingers.

Check that the valve returns to the specified

position when releasing fingers.

Does the valve return to the

specified position? Standard

value: 3 mm (0.12 in) from fully

closed position

Repair the poor

contact of ECM

connector.

Replace the elec-

tronic throttle con-

trol. <Ref. to FU(w/

o STI)-15, Throttle

Body.>

Step Check Yes No

15WRX_STI_US_EN.book 428 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-429

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FN:DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-196, DTC P2102 THROTTLE ACTUATOR CONTROL

MOTOR CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

• Engine stalls.

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 429 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-430

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK ELECTRONIC THROTTLE CON-

TROL RELAY.

1) Turn the ignition switch to OFF.

2) Remove the electronic throttle control relay.

3) Connect the battery to terminals No. 16 and

No. 17 of electronic throttle control relay.

4) Measure the resistance between electronic

throttle control relay terminals.

Terminals

No. 14 — No. 15:

Is the resistance less than 1 Ω? Go to step 2. Replace the elec-

tronic throttle con-

trol relay. <Ref. to

FU(w/o STI)-139,

Electronic Throttle

Control Relay.>

2 CHECK POWER SUPPLY OF ELECTRONIC

THROTTLE CONTROL RELAY.

Measure the voltage between electronic throttle

control relay connector and chassis ground.

Connector & terminal

(B225) No. 15 (+) — Chassis ground (–):

Is the voltage 10 V or more? Go to step 3. Repair the open or

ground short circuit

of power supply

circuit.

3 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

1) Disconnect the connector from ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between electronic

throttle control relay connector and chassis

ground.

Connector & terminal

(B225) No. 17 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control relay con-

nector.

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

1) Turn the ignition switch to OFF.

2) Measure the resistance between electronic

throttle control relay connector and chassis

ground.

Connector & terminal

(B225) No. 14 — Chassis ground:

(B225) No. 17 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and electronic

throttle control

relay connector.

5 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

Measure the resistance between ECM connec-

tor and electronic throttle control relay connec-

tor.

Connector & terminal

(B135) No. 39 — (B225) No. 17:

(B135) No. 11 — (B225) No. 14:

Is the resistance less than 1 Ω? Repair the poor

contact of ECM

connector.

Repair the open

circuit in harness

between ECM con-

nector and elec-

tronic throttle

control relay con-

nector.

15WRX_STI_US_EN.book 430 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-431

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FO:DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-198, DTC P2103 THROTTLE ACTUATOR CONTROL

MOTOR CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 431 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-432

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FP:DTC P2109 THROTTLE/PEDAL POSITION SENSOR “A” MINIMUM STOP

PERFORMANCE

NOTE:

For the diagnostic procedure, refer to DTC P2101. <Ref. to EN(w/o STI)(diag)-423, DTC P2101 THROTTLE

ACTUATOR CONTROL MOTOR CIRCUIT RANGE/PERFORMANCE, Diagnostic Procedure with Diagnos-

tic Trouble Code (DTC).>

FQ:DTC P2119 THROTTLE ACTUATOR CONTROL THROTTLE BODY RANGE/

PERFORMANCE

NOTE:

For the diagnostic procedure, refer to DTC P2101. <Ref. to EN(w/o STI)(diag)-423, DTC P2101 THROTTLE

ACTUATOR CONTROL MOTOR CIRCUIT RANGE/PERFORMANCE, Diagnostic Procedure with Diagnos-

tic Trouble Code (DTC).>

Step Check Yes No

1 CHECK ELECTRONIC THROTTLE CON-

TROL RELAY.

1) Turn the ignition switch to OFF.

2) Remove the electronic throttle control relay.

3) Measure the resistance between electronic

throttle control relay terminals.

Terminals

No. 14 — No. 15:

Is the resistance 1 MΩ or

more?

Go to step 2. Replace the elec-

tronic throttle con-

trol relay. <Ref. to

FU(w/o STI)-139,

Electronic Throttle

Control Relay.>

2 CHECK SHORT CIRCUIT OF ELECTRONIC

THROTTLE CONTROL RELAY POWER SUP-

PLY.

1) Turn the ignition switch to ON.

2) Measure the voltage between electronic

throttle control relay connector and chassis

ground.

Connector & terminal

(B225) No. 14 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control relay con-

nector.

Go to step 3.

3 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL RE-

LAY CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 39 — Engine ground:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of ECM

connector.

Repair the short

circuit to ground in

harness between

ECM connector

and electronic

throttle control

relay connector.

15WRX_STI_US_EN.book 432 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-433

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FR:DTC P2122 THROTTLE/PEDAL POSITION SENSOR/SWITCH “D” CIRCUIT

LOW INPUT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-202, DTC P2122 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “D” CIRCUIT LOW INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

56341

B315

B134A:

E159C:

B315

A17

A31

A30

A29

A19

A18

EN-10812

B122

J/C

B122

C25

C26

B22

A47

A35

C10

C17

C18

ECM

: TERMINAL No. OPTIONAL ARRANGEMENT

ACCELERATOR PEDAL

POSITION SENSOR

(BROWN)

(GRAY)

15WRX_STI_US_EN.book 433 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-434

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

accelerator pedal position sensor.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 30 — Engine ground:

(B134) No. 17 — Engine ground:

(B134) No. 17 — (B134) No. 19:

Is the resistance 1 MΩ or

more?

Go to step 2. Repair the short

circuit to ground in

harness between

ECM connector

and accelerator

pedal position sen-

sor connector.

2 CHECK SHORT CIRCUIT INSIDE THE ECM.

1) Connect the connector to ECM.

2) Measure the resistance between accelera-

tor pedal position sensor connector and chassis

ground.

Connector & terminal

(B315) No. 6 — Chassis ground:

Is the resistance 1 MΩ or

more?

Replace the accel-

erator pedal. <Ref.

to SP(w/o STI)-4,

Accelerator

Pedal.>

Repair the short

circuit to ground in

harness between

ECM connector

and accelerator

pedal position sen-

sor connector.

Replace the ECM if

defective. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

15WRX_STI_US_EN.book 434 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-435

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FS:DTC P2123 THROTTLE/PEDAL POSITION SENSOR/SWITCH “D” CIRCUIT

HIGH INPUT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-203, DTC P2123 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “D” CIRCUIT HIGH INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

56341

B315

B134A:

E159C:

B315

A17

A31

A30

A29

A19

A18

EN-10812

B122

J/C

B122

C25

C26

B22

A47

A35

C10

C17

C18

ECM

: TERMINAL No. OPTIONAL ARRANGEMENT

ACCELERATOR PEDAL

POSITION SENSOR

(BROWN)

(GRAY)

15WRX_STI_US_EN.book 435 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-436

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

accelerator pedal position sensor.

3) Measure the resistance of harness between

ECM connector and accelerator pedal position

sensor connector.

Connector & terminal

(B134) No. 17 — (B315) No. 6:

(B134) No. 31 — (B315) No. 5:

Is the resistance less than 1 Ω? Go to step 2. Repair the open

circuit of harness

between ECM con-

nector and accel-

erator pedal

position sensor

connector.

2 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Connect the connector to ECM.

2) Measure the resistance between accelera-

tor pedal position sensor connector and chassis

ground.

Connector & terminal

(B315) No. 5 — Chassis ground:

Is the resistance less than 5 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

ECM connector

• Poor contact of

coupling connector

3 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between accelerator

pedal position sensor connector and chassis

ground.

Connector & terminal

(B315) No. 6 (+) — Chassis ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power

supply in harness

between ECM con-

nector and accel-

erator pedal

position sensor

connector.

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(B134) No. 17 — (B134) No. 30:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of acceler-

ator pedal position

sensor connector.

Replace the accel-

erator pedal if

defective. <Ref. to

SP(w/o STI)-4,

Accelerator

Pedal.>

Repair the short

circuit to power

supply in harness

between ECM con-

nector and accel-

erator pedal

position sensor

connector.

15WRX_STI_US_EN.book 436 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-437

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FT:DTC P2127 THROTTLE/PEDAL POSITION SENSOR/SWITCH “E” CIRCUIT

LOW INPUT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-204, DTC P2127 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “E” CIRCUIT LOW INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

56341

B315

B134A:

E159C:

B315

A17

A31

A30

A29

A19

A18

EN-10812

B122

J/C

B122

C25

C26

B22

A47

A35

C10

C17

C18

ECM

: TERMINAL No. OPTIONAL ARRANGEMENT

ACCELERATOR PEDAL

POSITION SENSOR

(BROWN)

(GRAY)

15WRX_STI_US_EN.book 437 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-438

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

accelerator pedal position sensor.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(B134) No. 18 — Engine ground:

(B134) No. 29 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 2. Repair the short

circuit to ground in

harness between

ECM connector

and accelerator

pedal position sen-

sor connector.

2 CHECK SHORT CIRCUIT INSIDE THE ECM.

1) Connect the connector to ECM.

2) Measure the resistance between accelera-

tor pedal position sensor connector and chassis

ground.

Connector & terminal

(B315) No. 3 — Chassis ground:

Is the resistance 1 MΩ or

more?

Replace the accel-

erator pedal. <Ref.

to SP(w/o STI)-4,

Accelerator

Pedal.>

Repair the short

circuit to ground in

harness between

ECM connector

and accelerator

pedal position sen-

sor connector.

Replace the ECM if

defective. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

15WRX_STI_US_EN.book 438 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-439

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FU:DTC P2128 THROTTLE/PEDAL POSITION SENSOR/SWITCH “E” CIRCUIT

HIGH INPUT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-205, DTC P2128 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “E” CIRCUIT HIGH INPUT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

56341

B315

B134A:

E159C:

B315

A17

A31

A30

A29

A19

A18

EN-10812

B122

J/C

B122

C25

C26

B22

A47

A35

C10

C17

C18

ECM

: TERMINAL No. OPTIONAL ARRANGEMENT

ACCELERATOR PEDAL

POSITION SENSOR

(BROWN)

(GRAY)

15WRX_STI_US_EN.book 439 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-440

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

accelerator pedal position sensor.

3) Measure the resistance of harness between

ECM connector and accelerator pedal position

sensor connector.

Connector & terminal

(B134) No. 29 — (B315) No. 3:

(B134) No. 19 — (B315) No. 2:

Is the resistance less than 1 Ω? Go to step 2. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and accelerator

pedal position sen-

sor connector

• Poor contact of

joint connector

2 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Connect the connector to ECM.

2) Measure the resistance between accelera-

tor pedal position sensor connector and chassis

ground.

Connector & terminal

(B315) No. 2 — Chassis ground:

Is the resistance less than 1 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

ECM connector

• Poor contact of

coupling connector

3 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between accelerator

pedal position sensor connector and chassis

ground.

Connector & terminal

(B315) No. 3 (+) — Chassis ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power

supply in harness

between ECM con-

nector and accel-

erator pedal

position sensor

connector.

Go to step 4.

4 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(B134) No. 18 — (B134) No. 29:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of acceler-

ator pedal position

sensor connector.

Replace the accel-

erator pedal if

defective. <Ref. to

SP(w/o STI)-4,

Accelerator

Pedal.>

Repair the short

circuit to power

supply in harness

between ECM con-

nector and accel-

erator pedal

position sensor

connector.

15WRX_STI_US_EN.book 440 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-441

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FV:DTC P2135 THROTTLE/PEDAL POSITION SENSOR/SWITCH “A”/“B” VOLT-

AGE CORRELATION

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-206, DTC P2135 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “A”/“B” VOLTAGE CORRELATION, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

ECM

E158B:

B134A:

E159C:

11 12

19 21 222017

35 36

47 48

29 30

43 45 464441 42

15 1613 14

25 26

39 4037 38

E158

17 18

25 26

19 20

27 28

E159

123456

E57

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B22

5678

10 11 12

1413 15 16

B225

B550

215

317

B220

1011

E57

B17

B29

B18

B30

A39

A11

B225B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10800

C25

C26

B22

A47

A35

C10

C17

C18

232221 262524201918

587

10 11

B550

SBF-7

BATTERY

ELECTRONIC

THROTTLE

CONTROL

MAIN RELAY

FUSE HOLDER

ELECTRONIC

THROTTLE CONTROL

RELAY

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 441 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-442

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

electronic throttle control.

3) Measure the resistance between the ECM

connector and engine ground.

Connector & terminal

(E158) No. 18 — Engine ground:

(E158) No. 17 — Engine ground:

(E158) No. 29 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 2. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

2 CHECK SHORT CIRCUIT INSIDE THE ECM.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 1 — Engine ground:

(E57) No. 4 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 3. Repair the ground

short circuit of har-

ness between

ECM connector

and electronic

throttle control

connector.

Replace the ECM if

defective. <Ref. to

FU(w/o STI)-132,

Engine Control

Module (ECM).>

3 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance of harness between

ECM connector and electronic throttle control

connector.

Connector & terminal

(E158) No. 17 — (E57) No. 1:

(E158) No. 30 — (E57) No. 3:

(E158) No. 29 — (E57) No. 4:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit of harness

between ECM con-

nector and elec-

tronic throttle

control connector.

4 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Connect the connector to ECM.

2) Measure the resistance between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 3 — Engine ground:

Is the resistance less than 5 Ω? Go to step 5. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

ECM connector

• Poor contact of

coupling connector

5 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between electronic

throttle control connector and engine ground.

Connector & terminal

(E57) No. 1 (+) — Engine ground (–):

(E57) No. 4 (+) — Engine ground (–):

Is the voltage 5 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Go to step 6.

15WRX_STI_US_EN.book 442 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-443

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

6 CHECK HARNESS BETWEEN ECM AND

ELECTRONIC THROTTLE CONTROL CON-

NECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nectors.

Connector & terminal

(E158) No. 18 — (E158) No. 17:

(E158) No. 18 — (E158) No. 29:

Is the resistance 1 MΩ or

more?

Repair the poor

contact of elec-

tronic throttle con-

trol connector.

Replace the elec-

tronic throttle con-

trol if defective.

<Ref. to FU(w/o

STI)-15, Throttle

Body.>

Repair the short

circuit to power in

the harness

between ECM con-

nector and elec-

tronic throttle

control connector.

Step Check Yes No

15WRX_STI_US_EN.book 443 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-444

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FW:DTC P2138 THROTTLE/PEDAL POSITION SENSOR/SWITCH “D”/“E” VOLT-

AGE CORRELATION

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-207, DTC P2138 THROTTLE/PEDAL POSITION SEN-

SOR/SWITCH “D”/“E” VOLTAGE CORRELATION, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Improper idling

• Poor driving performance

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

56341

B315

B134A:

E159C:

B315

A17

A31

A30

A29

A19

A18

EN-10812

B122

J/C

B122

C25

C26

B22

A47

A35

C10

C17

C18

ECM

: TERMINAL No. OPTIONAL ARRANGEMENT

ACCELERATOR PEDAL

POSITION SENSOR

(BROWN)

(GRAY)

15WRX_STI_US_EN.book 444 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-445

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK ACCELERATOR PEDAL POSITION

SENSOR OUTPUT.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

Main accelerator pedal position sensor

signal

(B134) No. 17 (+) — Engine ground (–):

Sub accelerator pedal position sensor

signal

(B134) No. 29 (+) — Engine ground (–):

Is the difference in measured

values for the main accelerator

pedal position sensor signal

and the sub accelerator pedal

position sensor signal 0 V?

Go to step 3. Go to step 2.

2 CHECK ACCELERATOR PEDAL POSITION

SENSOR OUTPUT.

1) Measure the voltage between accelerator

pedal position sensor connector and chassis

ground.

Connector & terminal

(B315) No. 6 (+) — Chassis ground (–):

(B315) No. 3 (+) — Chassis ground (–):

Is the difference in measured

values for the main accelerator

pedal position sensor signal

and the sub accelerator pedal

position sensor signal 0 V?

Replace the accel-

erator pedal. <Ref.

to SP(w/o STI)-4,

Accelerator

Pedal.>

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and accelerator

pedal position sen-

sor connector

• Short circuit to

ground in harness

between ECM con-

nector and accel-

erator pedal

position sensor

connector

3 CHECK HARNESS BETWEEN ECM AND AC-

CELERATOR PEDAL POSITION SENSOR

CONNECTOR.

Measure the resistance of harness between the

accelerator pedal position sensor connector

and chassis ground.

Connector & terminal

(B315) No. 5 — Chassis ground:

(B315) No. 2 — Chassis ground:

Is the resistance less than 5 Ω? Repair the poor

contact of ECM

connector.

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit of

harness between

ECM connector

and accelerator

pedal position sen-

sor connector

• Open circuit of

harness between

ECM connector

and engine ground

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 445 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-446

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FX:DTC P2146 FUEL INJECTOR POWER SUPPLY A OPEN CIRCUIT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-209, DTC P2146 FUEL INJECTOR POWER SUPPLY A

OPEN CIRCUIT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK INPUT VOLTAGE OF ECM.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and engine ground.

Connector & terminal

(B134) No. 36 (+) — Engine ground (–):

(B134) No. 48 (+) — Engine ground (–):

Is the voltage 10 V or more? Repair the poor

contact of ECM

connector.

Go to step 2.

B564

12 13 14

2221

1817

10 11

7698

F27

B: B143

1234 56789

10 11 12 13 14 15 16 17 18 19 20

F35C:

6789

10 11 12

12 3

4567

F36E:B144

B143

F27

B134

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

EN-10832

B564

F35

B144

F36

M/B

SBF-5

ECM

FUEL INJECTOR

RELAY

BATTERY

(BROWN)

RELAY HOLDER

15WRX_STI_US_EN.book 446 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-447

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

2 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR RELAY CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Remove the fuel injector relay.

4) Measure the resistance between fuel injec-

tor relay connector and engine ground.

Connector & terminal

(B564) No. 12 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 3. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

relay connector.

3 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR RELAY CONNECTOR.

Measure the resistance of harness between

ECM connector and fuel injector relay connec-

tor.

Connector & terminal

(B134) No. 36 — (B564) No. 12:

(B134) No. 48 — (B564) No. 12:

(B134) No. 38 — (B564) No. 9:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit in harness

between ECM con-

nector and fuel

injector relay con-

nector.

4 CHECK INPUT VOLTAGE OF FUEL INJEC-

TOR RELAY.

Measure the voltage between fuel injector relay

connector and the engine ground.

Connector & terminal

(B564) No. 13 (+) — Engine ground (–):

(B564) No. 11 (+) — Engine ground (–):

Is the voltage 10 V or more? Replace the fuel

injector relay. <Ref.

to FU(w/o STI)-

143, Fuel Injector

Relay.>

Repair the open or

ground short circuit

of harness of

power supply cir-

cuit.

Step Check Yes No

15WRX_STI_US_EN.book 447 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-448

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FY:DTC P2158 VEHICLE SPEED SENSOR "B"

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-210, DTC P2158 VEHICLE SPEED SENSOR "B", Diag-

nostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK DTC OF VDC.

Check DTC of VDC.

Is DTC of VDC displayed? Perform the diag-

nosis according to

DTC. <Ref. to

VDC(diag)-42, List

of Diagnostic Trou-

ble Code (DTC).>

Repair the poor

contact of ECM

connector.

15WRX_STI_US_EN.book 448 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-449

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

FZ:DTC P2195 O2 SENSOR SIGNAL BIASED/STUCK LEAN (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-211, DTC P2195 O2 SENSOR SIGNAL BIASED/

STUCK LEAN (BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 449 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-450

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FRONT OXYGEN (A/F) SENSOR

CONNECTOR AND COUPLING CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

front oxygen (A/F) sensor.

3) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

Is the resistance less than 1 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector

• Poor contact of

coupling connector

3 CHECK FOR POOR CONTACT.

Check for poor contact of the front oxygen (A/F)

sensor connector.

Is there poor contact of front

oxygen (A/F) sensor connec-

tor?

Repair the poor

contact of front

oxygen (A/F) sen-

sor connector.

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

15WRX_STI_US_EN.book 450 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-451

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GA:DTC P2196 O2 SENSOR SIGNAL BIASED/STUCK RICH (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-213, DTC P2196 O2 SENSOR SIGNAL BIASED/

STUCK RICH (BANK 1 SENSOR 1), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 451 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-452

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FRONT OXYGEN (A/F) SENSOR

CONNECTOR AND COUPLING CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance between ECM con-

nector and chassis ground.

Connector & terminal

(E158) No. 15 — Chassis ground:

(E158) No. 27 — Chassis ground:

(E158) No. 39 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 3. Repair the short

circuit to ground in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector.

3 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Connect the connector to ECM.

2) Disconnect the connectors from front oxy-

gen (A/F) sensor.

3) Turn the ignition switch to ON.

4) Measure the voltage between ECM connec-

tor and chassis ground.

Connector & terminal

(E158) No. 15 (+) — Chassis ground (–):

(E158) No. 27 (+) — Chassis ground (–):

(E158) No. 39 (+) — Chassis ground (–):

Is the voltage 8 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

Repair the poor

contact of ECM

connector.

15WRX_STI_US_EN.book 452 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-453

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GB:DTC P219A BANK 1 AIR-FUEL RATIO IMBALANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-215, DTC P219A BANK 1 AIR-FUEL RATIO IMBAL-

ANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

• Engine stalls.

• Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

15WRX_STI_US_EN.book 453 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-454

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

465

E24

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E24

B550

418

B225

B22

5678

10 11 12

1413 15 16

B39

B15

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10797

4B27

B134A:

E158B:

C: E159

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

FRONT OXYGEN (A/F) SENSOR

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 454 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-455

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 455 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-456

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FRONT OXYGEN (A/F) SENSOR

CONNECTOR AND COUPLING CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connectors from ECM and

front oxygen (A/F) sensor.

3) Measure the resistance of harness between

ECM connector and front oxygen (A/F) sensor

connector.

Connector & terminal

(E158) No. 15 — (E24) No. 1:

(E158) No. 27 — (E24) No. 4:

(E158) No. 39 — (E24) No. 5:

Is the resistance less than 1 Ω? Go to step 3. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector

• Poor contact of

coupling connector

E17

E16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B11

B23

B35

EN-10794

E16

E17

B47

B12

B24

B36

B48

C18

C17

C10

A35

A47

B22

C26

C25

B134A:

E158B:

C: E159

ECM

FUEL INJECTOR No. 4

FUEL INJECTOR No. 3

FUEL INJECTOR No. 2

FUEL INJECTOR No. 1

(BROWN)

(GRAY)

(BLACK)

15WRX_STI_US_EN.book 456 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-457

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

3 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

Measure the resistance between ECM connec-

tor and chassis ground.

Connector & terminal

(E158) No. 15 — Chassis ground:

(E158) No. 27 — Chassis ground:

(E158) No. 39 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair the short

circuit to ground in

harness between

ECM connector

and front oxygen

(A/F) sensor con-

nector.

4 CHECK HARNESS BETWEEN ECM AND

FRONT OXYGEN (A/F) SENSOR CONNEC-

TOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between front oxygen

(A/F) sensor connector and chassis ground.

Connector & terminal

(E24) No. 1 (+) — Chassis ground (–):

(E24) No. 4 (+) — Chassis ground (–):

(E24) No. 5 (+) — Chassis ground (–):

Is the voltage 8 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and front

oxygen (A/F) sen-

sor connector.

Go to step 5.

5 CHECK EXHAUST SYSTEM. Are there holes or loose bolts

on exhaust system?

Repair the exhaust

system.

Go to step 6.

6 CHECK AIR INTAKE SYSTEM. Are there holes, loose bolts or

disconnection of hose on air

intake system?

Repair the air

intake system.

Go to step 7.

7 CHECK FUEL PRESSURE.

WARNING:

Place “NO OPEN FLAMES” signs near the

working area.

CAUTION:

Be careful not to spill fuel.

1) Connect the front oxygen (A/F) sensor con-

nector.

2) Measure the fuel pressure. <Ref. to ME(w/o

STI)-31, INSPECTION, Fuel Pressure.>

CAUTION:

Release fuel pressure before removing the

fuel pressure gauge.

Is the measured value 328 —

358 kPa (3.3 — 3.7 kgf/cm

, 48

— 52 psi)?

Go to step 8. Check the fuel

pump and fuel

delivery line. <Ref.

to FU(w/o STI)-

172, INSPEC-

TION, Fuel

Pump.> <Ref. to

FU(w/o STI)-201,

INSPECTION,

Fuel Delivery and

Evaporation

Lines.>

8 CHECK ENGINE COOLANT TEMPERATURE

SENSOR.

1) Start the engine and warm up completely.

2) Read the value of «Coolant Temp.» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Coolant Temp.»

75°C (167°F) or more?

Go to step 9. Replace the

engine coolant

temperature sen-

sor. <Ref. to FU(w/

o STI)-93, Engine

Coolant Tempera-

ture Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 457 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-458

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

9 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Read the value of «Mass Air Flow» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Mass Air

Flow» 2.0 — 5.0 g/s (0.26 —

0.66 lb/m)?

Go to step 10. Replace the mass

air flow and intake

air temperature

sensor. <Ref. to

FU(w/o STI)-118,

Mass Air Flow and

Intake Air Temper-

ature Sensor.>

10 CHECK MASS AIR FLOW AND INTAKE AIR

TEMPERATURE SENSOR.

1) Start the engine and warm up engine until

coolant temperature is higher than 75°C

(167°F).

2) For CVT models, set the select lever to “P”

range or “N” range, and for MT models, place

the shift lever in the neutral position.

3) Turn the A/C switch to OFF.

4) Turn all the accessory switches to OFF.

5) Open the front hood.

6) Measure the ambient temperature.

7) Read the value of «IAT Sensor #11» using

the Subaru Select Monitor or a general scan

tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Subtract ambient temperature

value from the value of «IAT

Sensor #11». Is the obtained

value –10 — 50°C (–18 —

90°F)?

Go to step 11. Check the mass air

flow and intake air

temperature sen-

sor. <Ref. to FU(w/

o STI)-118, Mass

Air Flow and Intake

Air Temperature

Sensor.>

Step Check Yes No

15WRX_STI_US_EN.book 458 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-459

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

11 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

keep the engine speed at 3,000 rpm. (2 minutes

maximum)

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.490 V or more?

Go to step 12. Go to step 13.

12 CHECK REAR OXYGEN SENSOR DATA.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), and

rapidly reduce the engine speed from 3,000

rpm.

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» 0.250 V or less?

Go to step 14. Go to step 13.

13 CHECK REAR OXYGEN SENSOR CONNEC-

TOR AND COUPLING CONNECTOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 15.

14 CHECK FRONT OXYGEN (A/F) SENSOR US-

ING REAR OXYGEN SENSOR SIGNAL.

1) Warm up the engine until engine coolant

temperature is higher than 75°C (167°F), then

keep the engine idling for 5 minutes or more.

2) Read the value of «Oxygen sensor #12»

using the Subaru Select Monitor or a general

scan tool.

NOTE:

• Subaru Select Monitor

For detailed operation procedures, refer to

“READ CURRENT DATA FOR ENGINE”. <Ref.

to EN(w/o STI)(diag)-37, Subaru Select Moni-

tor.>

• General scan tool

For detailed operation procedures, refer to the

general scan tool operation manual.

Is the value of «Oxygen sensor

#12» kept at 0.250 V or less for

5 minutes or more?

Replace the front

oxygen (A/F) sen-

sor. <Ref. to FU(w/

o STI)-126, Front

Oxygen (A/F) Sen-

sor.>

Go to step 15.

Step Check Yes No

15WRX_STI_US_EN.book 459 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-460

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

15 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 16. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and rear oxygen

sensor connector

• Poor contact of

coupling connector

16 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between rear oxygen

sensor connector and chassis ground.

Connector & terminal

(E25) No. 4 (+) — Chassis ground (–):

Is the voltage 0.2 — 0.5 V? Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

Go to step 17.

17 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from fuel injector

on faulty cylinders.

3) Measure the resistance between fuel injec-

tor connector and engine ground on faulty cylin-

ders.

Connector & terminal

#1 (E5) No. 1 — Engine ground:

#1 (E5) No. 2 — Engine ground:

#2 (E16) No. 1 — Engine ground:

#2 (E16) No. 2 — Engine ground:

#3 (E6) No. 1 — Engine ground:

#3 (E6) No. 2 — Engine ground:

#4 (E17) No. 1 — Engine ground:

#4 (E17) No. 2 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 18. Repair the short

circuit to ground in

harness between

ECM connector

and fuel injector

connector.

18 CHECK HARNESS BETWEEN ECM AND

FUEL INJECTOR CONNECTOR.

Measure the resistance of harness between

ECM and fuel injector connector on faulty cylin-

ders.

Connector & terminal

#1 (E158) No. 12 — (E5) No. 1:

#1 (E158) No. 11 — (E5) No. 2:

#2 (E158) No. 24 — (E16) No. 1:

#2 (E158) No. 23 — (E16) No. 2:

#3 (E158) No. 36 — (E6) No. 1:

#3 (E158) No. 35 — (E6) No. 2:

#4 (E158) No. 48 — (E17) No. 1:

#4 (E158) No. 47 — (E17) No. 2:

Is the resistance less than 1 Ω? Go to step 19. Repair the open

circuit of the har-

ness between the

ECM connector

and fuel injector

connector.

19 CHECK FUEL INJECTOR.

Check the fuel injector on faulty cylinder. <Ref.

to FU(w/o STI)-70, INSPECTION, Fuel Injec-

tor.>

Are fuel injectors OK? Go to step 20. Replace the faulty

fuel injector. <Ref.

to FU(w/o STI)-51,

Fuel Injector.>

Step Check Yes No

15WRX_STI_US_EN.book 460 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-461

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

20 CHECK INSTALLATION CONDITION OF

CAMSHAFT POSITION SENSOR/CRANK-

SHAFT POSITION SENSOR.

Is the camshaft position sensor

or crankshaft position sensor

loosely installed?

Tighten the cam-

shaft position sen-

sor or crankshaft

position sensor.

<Ref. to FU(w/o

STI)-104, INSTAL-

LATION, Cam-

shaft Position

Sensor.> <Ref. to

FU(w/o STI)-99,

INSTALLATION,

Crankshaft Posi-

tion Sensor.>

Go to step 21.

21 CHECK CRANKSHAFT POSITION SENSOR

PLATE.

Is the crankshaft position sen-

sor plate rusted or does it have

broken teeth?

Replace the crank-

shaft position sen-

sor plate. <Ref. to

ME(w/o STI)-260,

Cylinder Block.>

Go to step 22.

22 CHECK INSTALLATION CONDITION OF

TIMING CHAIN.

Turn the crankshaft using ST, and align the

alignment mark on crank sprocket with align-

ment mark on cylinder block.

ST 18252AA000 CRANKSHAFT

SOCKET

Is the timing chain dislocated

from its proper position?

Correct the instal-

lation condition of

timing chain. <Ref.

to ME(w/o STI)-

116, Timing Chain

Assembly.>

Go to step 23.

23 CHECK FUEL LEVEL. Is the fuel meter indication

higher than the “Lower” level?

Go to step 24. Refill the fuel so

that the fuel meter

indication is higher

than the “Lower”

level, and proceed

to the next step. Go

to step 24.

24 CHECK STATUS OF MALFUNCTION INDI-

CATOR LIGHT.

1) Clear the memory using the Subaru Select

Monitor or general scan tool. <Ref. to EN(w/o

STI)(diag)-61, Clear Memory Mode.>

2) Start the engine, and drive the vehicle 10

minutes or more.

Does the malfunction indicator

light illuminate or blink?

Go to step 26. Go to step 25.

25 CHECK CAUSE OF MISFIRE. Was the cause of misfire identi-

fied when the engine is run-

ning?

Finish diagnostics

operation, if the

engine has no

abnormality.

Repair the poor

contact of connec-

tor.

NOTE:

In this case, repair

the following item:

• Poor contact of

ignition coil con-

nector

• Poor contact of

fuel injector con-

nector on faulty

cylinders

• Poor contact of

ECM connector

• Poor contact of

coupling connector

Step Check Yes No

15WRX_STI_US_EN.book 461 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-462

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

26 CHECK AIR INTAKE SYSTEM. Is there any fault in air intake

system?

Repair the air

intake system.

NOTE:

Check the follow-

ing items.

• Are there air

leaks or air suction

caused by loose or

dislocated nuts

and bolts?

• Are there cracks

or any disconnec-

tion of hoses?

Go to step 27.

27 CHECK MISFIRE SYMPTOM.

1) Turn the ignition switch to ON.

2) Check for DTC. <Ref. to EN(w/o STI)(diag)-

46, Read Diagnostic Trouble Code (DTC).>

Does the Subaru Select Moni-

tor or general scan tool indicate

only one DTC?

Go to step 30. Go to step 28.

28 CHECK DTC. Is DTC P0301 and P0303 dis-

played on the Subaru Select

Monitor or general scan tool?

Go to step 31. Go to step 29.

29 CHECK DTC. Is DTC P0302 and P0304 dis-

played on the Subaru Select

Monitor or general scan tool?

Go to step 32. Go to step 33.

30 ONLY ONE CYLINDER. Is there any fault in the cylin-

der?

Repair or replace

faulty parts.

NOTE:

Check the follow-

ing items.

• Spark plug

• Ignition coil

• Fuel injector

• Compression ra-

tio

Go to DTC P0171.

<Ref. to EN(w/o

STI)(diag)-185,

DTC P0171 SYS-

TEM TOO LEAN

(BANK 1), Diag-

nostic Procedure

with Diagnostic

Trouble Code

(DTC).>

31 GROUP OF #1 AND #3 CYLINDERS. Are there any faults in #1 and

#3 cylinders?

Repair or replace

faulty parts.

NOTE:

Check the follow-

ing items.

• Spark plug

• Ignition coil

• Fuel injector

• Compression ra-

tio

• Skipping timing

chain teeth

Go to DTC P0171.

<Ref. to EN(w/o

STI)(diag)-185,

DTC P0171 SYS-

TEM TOO LEAN

(BANK 1), Diag-

nostic Procedure

with Diagnostic

Trouble Code

(DTC).>

32 GROUP OF #2 AND #4 CYLINDERS. Are there any faults in #2 and

#4 cylinders?

Repair or replace

faulty parts.

NOTE:

Check the follow-

ing items.

• Spark plug

• Ignition coil

• Fuel injector

• Compression ra-

tio

• Skipping timing

chain teeth

Go to DTC P0171.

<Ref. to EN(w/o

STI)(diag)-185,

DTC P0171 SYS-

TEM TOO LEAN

(BANK 1), Diag-

nostic Procedure

with Diagnostic

Trouble Code

(DTC).>

Step Check Yes No

15WRX_STI_US_EN.book 462 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-463

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

33 CYLINDER AT RANDOM. Is the engine idle rough? Go to DTC P0171.

<Ref. to EN(w/o

STI)(diag)-185,

DTC P0171 SYS-

TEM TOO LEAN

(BANK 1), Diag-

nostic Procedure

with Diagnostic

Trouble Code

(DTC).>

Repair or replace

faulty parts.

NOTE:

Check the follow-

ing items.

• Spark plug

• Ignition coil

• Fuel injector

• Compression ra-

tio

Step Check Yes No

15WRX_STI_US_EN.book 463 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-464

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GC:DTC P2227 BAROMETRIC PRESSURE CIRCUIT RANGE/PERFORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-220, DTC P2227 BAROMETRIC PRESSURE CIRCUIT

RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

GD:DTC P2228 BAROMETRIC PRESSURE CIRCUIT LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-221, DTC P2228 BAROMETRIC PRESSURE CIRCUIT

LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

NOTE:

The barometric

pressure sensor is

built into the ECM.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

NOTE:

The barometric

pressure sensor is

built into the ECM.

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EN(w/o STI)(diag)-465

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GE:DTC P2229 BAROMETRIC PRESSURE CIRCUIT HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-222, DTC P2229 BAROMETRIC PRESSURE CIRCUIT

HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

NOTE:

The barometric

pressure sensor is

built into the ECM.

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EN(w/o STI)(diag)-466

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GF:DTC P2270 O2 SENSOR SIGNAL BIASED/STUCK LEAN (BANK 1 SENSOR 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-223, DTC P2270 O2 SENSOR SIGNAL BIASED/

STUCK LEAN (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 466 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-467

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK REAR OXYGEN SENSOR CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

3 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Connect the connector to ECM.

2) Turn the ignition switch to ON.

3) Measure the voltage between rear oxygen

sensor connector and engine ground.

Connector & terminal

(E25) No. 3 (+) — Engine ground (–):

Is the voltage 0.15 V or more? Repair the short

circuit to power in

the harness

between ECM con-

nector and rear

oxygen sensor

connector.

Go to step 4.

4 CHECK EXHAUST SYSTEM.

Check exhaust system parts.

NOTE:

Check the following items.

• Looseness and improper fitting of exhaust

system parts

• Damage (crack, hole etc.) of parts

• Damage (crack, hole etc.) between front oxy-

gen (A/F) sensor and rear oxygen sensor

Is there any fault in exhaust

system?

Repair or replace

faulty parts.

Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

15WRX_STI_US_EN.book 467 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-468

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GG:DTC P2271 O2 SENSOR SIGNAL BIASED/STUCK RICH (BANK 1 SENSOR 2)

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-225, DTC P2271 O2 SENSOR SIGNAL BIASED/

STUCK RICH (BANK 1 SENSOR 2), Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

E25

B550

418

B225

B22

5678

10 11 12

1413 15 16

B16

B42

B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10798

B134A:

E158B:

C: E159

E25

C25

C26

B22

A47

A35

C10

C17

C18

SBF-5

ECM

232221 262524201918

587

10 11

B550

A/F,

OXYGEN SENSOR

RELAY

BATTERY

FUSE HOLDER

REAR OXYGEN SENSOR

(BROWN)

(GRAY)(BLACK)

15WRX_STI_US_EN.book 468 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-469

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK REAR OXYGEN SENSOR CONNEC-

TOR.

Has water entered the connec-

tor?

Completely

remove any water

inside.

Go to step 2.

2 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

rear oxygen sensor.

3) Measure the resistance of harness between

ECM connector and rear oxygen sensor con-

nector.

Connector & terminal

(E158) No. 42 — (E25) No. 3:

(E158) No. 16 — (E25) No. 4:

Is the resistance less than 1 Ω? Go to step 3. Repair the open

circuit of harness

between ECM con-

nector and rear

oxygen sensor

connector.

3 CHECK HARNESS BETWEEN ECM AND

REAR OXYGEN SENSOR CONNECTOR.

Measure the resistance between the ECM con-

nector and engine ground.

Connector & terminal

(E158) No. 42 — Engine ground:

Is the resistance 1 MΩ or

more?

Go to step 4. Repair the short

circuit to ground in

harness between

ECM connector

and rear oxygen

sensor connector.

4 CHECK EXHAUST SYSTEM.

Check exhaust system parts.

NOTE:

Check the following items.

• Looseness and improper fitting of exhaust

system parts

• Damage (crack, hole etc.) of parts

• Damage (crack, hole etc.) between front oxy-

gen (A/F) sensor and rear oxygen sensor

Is there any fault in exhaust

system?

Repair or replace

faulty parts.

Replace the rear

oxygen sensor.

<Ref. to FU(w/o

STI)-128, Rear

Oxygen Sensor.>

15WRX_STI_US_EN.book 469 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-470

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GH:DTC P2401 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP

CONTROL CIRCUIT LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-226, DTC P2401 EVAPORATIVE EMISSION SYSTEM

LEAK DETECTION PUMP CONTROL CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B97

1234 56789

10 11 12 13 14 15 16 17 18 19 20

B122

EN-10808

R1B97

B122

J/C

R400

1234

5678

R400

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

B134

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BROWN)

VACUUM

PUMP

MAIN RELAY

BATTERY

FUSE HOLDER

LEAK CHECK VALVE ASSY

SWITCHING

VALVE

PRESSURE

SENSOR

: TERMINAL No. OPTIONAL ARRANGEMENT

15WRX_STI_US_EN.book 470 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-471

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and chassis ground.

Connector & terminal

(B134) No. 3 (+) — Chassis ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary open or

short circuit of har-

ness or temporary

poor contact of

connector may be

the cause.

3 CHECK POWER SUPPLY TO LEAK CHECK

VALVE ASSEMBLY.

Measure the voltage between the leak check

valve assembly connector and engine ground.

Connector & terminal

(R400) No. 3 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the leak check valve assembly.

3) Measure the resistance between leak check

valve assembly and chassis ground.

Connector & terminal

(R400) No. 4 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and leak check

valve assembly

connector.

5 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

Measure the resistance of harness between

ECM connector and the leak check valve

assembly connector.

Connector & terminal

(B134) No. 3 — (R400) No. 4:

Is the resistance less than 1 Ω? Go to step 6. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and the leak check

valve assembly

connector

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 471 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-472

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

6 CHECK LEAK CHECK VALVE ASSEMBLY.

Check the vacuum pump of the leak check valve

assembly. <Ref. to EC(w/o STI)-70, CHECK

VACUUM PUMP, INSPECTION, Leak Check

Valve Assembly.>

Is the vacuum pump of the leak

check valve assembly OK?

Repair the poor

contact in the leak

check valve

assembly connec-

tor.

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

Step Check Yes No

15WRX_STI_US_EN.book 472 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-473

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GI: DTC P2402 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP

CONTROL CIRCUIT HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-227, DTC P2402 EVAPORATIVE EMISSION SYSTEM

LEAK DETECTION PUMP CONTROL CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B97

1234 56789

10 11 12 13 14 15 16 17 18 19 20

B122

EN-10808

R1B97

B122

J/C

R400

1234

5678

R400

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

B134

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BROWN)

VACUUM

PUMP

MAIN RELAY

BATTERY

FUSE HOLDER

LEAK CHECK VALVE ASSY

SWITCHING

VALVE

PRESSURE

SENSOR

: TERMINAL No. OPTIONAL ARRANGEMENT

15WRX_STI_US_EN.book 473 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-474

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the leak

check valve assembly.

3) Turn the ignition switch to ON.

4) Measure the voltage between leak check

valve assembly and chassis ground.

Connector & terminal

(R400) No. 4 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

harness between

ECM connector

and leak check

valve assembly

connector.

Go to step 2.

2 CHECK LEAK CHECK VALVE ASSEMBLY.

1) Turn the ignition switch to OFF.

2) Check the vacuum pump of the leak check

valve assembly. <Ref. to EC(w/o STI)-70,

CHECK VACUUM PUMP, INSPECTION, Leak

Check Valve Assembly.>

Is the vacuum pump of the leak

check valve assembly OK?

Repair the poor

contact in the leak

check valve

assembly connec-

tor.

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

15WRX_STI_US_EN.book 474 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-475

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GJ:DTC P2404 EVAPORATIVE EMISSION SYSTEM LEAK DETECTION PUMP

SENSE CIRCUIT RANGE/PERFORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-228, DTC P2404 EVAPORATIVE EMISSION SYSTEM

LEAK DETECTION PUMP SENSE CIRCUIT RANGE/PERFORMANCE, Diagnostic Trouble Code (DTC)

Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B97

1234 56789

10 11 12 13 14 15 16 17 18 19 20

B122

EN-10808

R1B97

B122

J/C

R400

1234

5678

R400

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

B134

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BROWN)

VACUUM

PUMP

MAIN RELAY

BATTERY

FUSE HOLDER

LEAK CHECK VALVE ASSY

SWITCHING

VALVE

PRESSURE

SENSOR

: TERMINAL No. OPTIONAL ARRANGEMENT

15WRX_STI_US_EN.book 475 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-476

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check the appro-

priate DTC using

the “List of Diag-

nostic Trouble

Code (DTC)”.

<Ref. to EN(w/o

STI)(diag)-85, List

of Diagnostic Trou-

ble Code (DTC).>

Go to step 2.

2 CHECK ELCM PUMP.

Operate the ELCM pump using the Subaru

Select Monitor.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

Does the ELCM pump operate? Go to step 6. Go to step 3.

3 CHECK POWER SUPPLY OF LEAK CHECK

VALVE ASSEMBLY.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the leak

check valve assembly.

3) Turn the ignition switch to ON.

4) Measure the voltage between the leak

check valve assembly connector and chassis

ground.

Connector & terminal

(R400) No. 3 (+) — Chassis ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

the main relay and

the leak check

valve assembly

connector

• Poor contact of

main relay connec-

tor

• Poor contact of

coupling connector

4 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and the leak check valve

assembly connector.

Connector & terminal

(B134) No. 3 — (R400) No. 4:

Is the resistance less than 1 Ω? Go to step 5. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and the leak check

valve assembly

connector

• Poor contact of

coupling connector

5 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Measure the resistance of harness between

ECM connector and chassis ground.

Connector & terminal

(B134) No. 3 — Chassis ground:

Is the resistance 1 MΩ or

more?

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

Repair the short

circuit to ground in

harness between

ECM connector

and leak check

valve assembly

connector.

6 CHECK ELCM SWITCHING VALVE.

Operate the ELCM switching valve using the

Subaru Select Monitor.

NOTE:

For detailed procedures, refer to “System Oper-

ation Check Mode”. <Ref. to EN(w/o STI)(diag)-

62, System Operation Check Mode.>

Does the ELCM switching valve

operate?

Go to step

10. Go to step 7.

15WRX_STI_US_EN.book 476 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-477

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

7 CHECK POWER SUPPLY OF LEAK CHECK

VALVE ASSEMBLY.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the leak

check valve assembly.

3) Turn the ignition switch to ON.

4) Measure the voltage between the leak

check valve assembly connector and chassis

ground.

Connector & terminal

(R400) No. 5 (+) — Chassis ground (–):

Is the voltage 10 V or more? Go to step 8. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

the main relay and

the leak check

valve assembly

connector

• Poor contact of

main relay connec-

tor

• Poor contact of

coupling connector

8 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM.

3) Measure the resistance of harness between

ECM connector and the leak check valve

assembly connector.

Connector & terminal

(B134) No. 27 — (R400) No. 1:

Is the resistance less than 1 Ω? Go to step 9. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and the leak check

valve assembly

connector

• Poor contact of

coupling connector

9 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Measure the resistance of harness between

ECM connector and chassis ground.

Connector & terminal

(B134) No. 27 — Chassis ground:

Is the resistance 1 MΩ or

more?

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

Repair the short

circuit to ground in

harness between

ECM connector

and leak check

valve assembly

connector.

10 CHECK EVAPORATIVE EMISSION CON-

TROL SYSTEM.

Perform drive cycle I. <Ref. to EN(w/o

STI)(diag)-56, DRIVE CYCLE I, PROCEDURE,

Drive Cycle.>

Is DTC P2404 displayed on the

display?

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary poor con-

tact of connector,

temporary open or

short circuit of har-

ness may be the

cause.

Step Check Yes No

15WRX_STI_US_EN.book 477 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-478

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GK:DTC P2419 EVAPORATIVE EMISSION SYSTEM SWITCHING VALVE CON-

TROL CIRCUIT LOW

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-229, DTC P2419 EVAPORATIVE EMISSION SYSTEM

SWITCHING VALVE CONTROL CIRCUIT LOW, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B97

1234 56789

10 11 12 13 14 15 16 17 18 19 20

B122

EN-10808

R1B97

B122

J/C

R400

1234

5678

R400

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

B134

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BROWN)

VACUUM

PUMP

MAIN RELAY

BATTERY

FUSE HOLDER

LEAK CHECK VALVE ASSY

SWITCHING

VALVE

PRESSURE

SENSOR

: TERMINAL No. OPTIONAL ARRANGEMENT

15WRX_STI_US_EN.book 478 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-479

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to ON.

2) Measure the voltage between ECM connec-

tor and chassis ground.

Connector & terminal

(B134) No. 27 (+) — Chassis ground (–):

Is the voltage 10 V or more? Go to step 2. Go to step 3.

2 CHECK FOR POOR CONTACT.

Check for poor contact of ECM connector.

Is there poor contact of ECM

connector?

Repair the poor

contact of ECM

connector.

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, tem-

porary open or

short circuit of har-

ness or temporary

poor contact of

connector may be

the cause.

3 CHECK POWER SUPPLY TO LEAK CHECK

VALVE ASSEMBLY.

Measure the voltage between the leak check

valve assembly connector and engine ground.

Connector & terminal

(R400) No. 5 (+) — Engine ground (–):

Is the voltage 10 V or more? Go to step 4. Repair the power

supply circuit.

4 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from ECM and

the leak check valve assembly.

3) Measure the resistance between leak check

valve assembly and chassis ground.

Connector & terminal

(R400) No. 1 — Chassis ground:

Is the resistance 1 MΩ or

more?

Go to step 5. Repair the short

circuit to ground in

harness between

ECM connector

and leak check

valve assembly

connector.

5 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

Measure the resistance of harness between

ECM connector and the leak check valve

assembly connector.

Connector & terminal

(B134) No. 27 — (R400) No. 1:

Is the resistance less than 1 Ω? Go to step 6. Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and the leak check

valve assembly

connector

• Poor contact of

coupling connector

15WRX_STI_US_EN.book 479 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-480

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

6 CHECK LEAK CHECK VALVE ASSEMBLY.

Check the switching valve of the leak check

valve assembly. <Ref. to EC(w/o STI)-68,

CHECK SWITCHING VALVE, INSPECTION,

Leak Check Valve Assembly.>

Is the switching valve of the

leak check valve assembly OK?

Repair the poor

contact in the leak

check valve

assembly connec-

tor.

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

Step Check Yes No

15WRX_STI_US_EN.book 480 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-481

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GL:DTC P2420 EVAPORATIVE EMISSION SYSTEM SWITCHING VALVE CON-

TROL CIRCUIT HIGH

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-230, DTC P2420 EVAPORATIVE EMISSION SYSTEM

SWITCHING VALVE CONTROL CIRCUIT HIGH, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B97

1234 56789

10 11 12 13 14 15 16 17 18 19 20

B122

EN-10808

R1B97

B122

J/C

R400

1234

5678

R400

B220

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

B550

215

B220

B134

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134

232221 262524201918

587

10 11

B550

ECM

SBF-7

(BROWN)

VACUUM

PUMP

MAIN RELAY

BATTERY

FUSE HOLDER

LEAK CHECK VALVE ASSY

SWITCHING

VALVE

PRESSURE

SENSOR

: TERMINAL No. OPTIONAL ARRANGEMENT

15WRX_STI_US_EN.book 481 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-482

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK HARNESS BETWEEN ECM AND

LEAK CHECK VALVE ASSEMBLY CONNEC-

TOR.

1) Turn the ignition switch to OFF.

2) Disconnect the connector from the leak

check valve assembly.

3) Turn the ignition switch to ON.

4) Measure the voltage between leak check

valve assembly and chassis ground.

Connector & terminal

(R400) No. 1 (+) — Chassis ground (–):

Is the voltage 10 V or more? Repair the short

circuit to power in

harness between

ECM connector

and leak check

valve assembly

connector.

Go to step 2.

2 CHECK LEAK CHECK VALVE ASSEMBLY.

1) Turn the ignition switch to OFF.

2) Check the switching valve of the leak check

valve assembly. <Ref. to EC(w/o STI)-68,

CHECK SWITCHING VALVE, INSPECTION,

Leak Check Valve Assembly.>

Is the switching valve of the

leak check valve assembly OK?

Repair the poor

contact in the leak

check valve

assembly connec-

tor.

Replace the leak

check valve

assembly. <Ref. to

EC(w/o STI)-54,

Leak Check Valve

Assembly.>

15WRX_STI_US_EN.book 482 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-483

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GM:DTC P2530 IGNITION SWITCH RUN POSITION CIRCUIT

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-231, DTC P2530 IGNITION SWITCH RUN POSITION

CIRCUIT, Diagnostic Trouble Code (DTC) Detecting Criteria.>

TROUBLE SYMPTOM:

Improper idling

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

B72

B550

923

B225

36 37

B22

5678

10 11 12

1413 15 16

17 18

25 26

19 20

27 28

E159

11 12

23 24

35 36

47 48

7894

4643 4441 4239 4037 38

2219 2017 1815 1613 14

3431 3229 3027 2825 26

B134A:

B550

215

B220

B134A:

E159C:

A32

A23

A38

A24

A12

B220 B225

10 11

14 15

19 21 22

32 33

28262423

36 37

41 43 44

EN-10792

C25

C26

B22

A47

A35

C10

C17

C18

B72

7856

3412

ECM

SBF-7

SBF-6

232221 262524201918

587

10 11

B550

: WITHOUT PUSH BUTTON START

: WITH PUSH BUTTON START

BATTERY

MAIN

RELAY

FUSE HOLDER

M/B No. 13

F/B No. 12

(BROWN)

(GRAY)

IG RELAY 1

(PUSH BUTTON

START)

FUSE HOLDER

IGNITION

SWITCH

MAIN SBF

15WRX_STI_US_EN.book 483 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-484

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

Step Check Yes No

1 CHECK ECM CONNECTOR.

Check the connecting condition of ECM con-

nector.

Is the ECM connector correctly

connected?

Go to step 2. Connect the ECM

connector cor-

rectly.

2 CHECK INPUT VOLTAGE OF ECM.

1) Turn the ignition switch to ON.

2) Connect the check board.

ST 18460AA030 CHECK BOARD

3) Measure the voltage between ECM connec-

tor and engine ground while wiggling the har-

ness between ECM connector and ignition

switch connector (for models without push but-

ton start), or between ECM connector and IG

relay 1 (push button start) connector (for mod-

els with push button start).

Connector & terminal

(B134) No. 32 (+) — Engine ground (–):

Is the voltage 8 V or more all the

time?

Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

NOTE:

In this case, the fol-

lowing items may

be the cause of

fault.

Model without

push button start

• Open or short

circuit to ground in

harness between

ECM connector

and ignition switch

connector

• Poor contact of

ignition switch con-

nector

• Poor contact of

ignition switch

Model with push

button start

• Open circuit or

short circuit to

ground in harness

between ECM con-

nector and IG relay

1 (push button

start) connector

• Poor contact in

IG relay 1 (push

button start) con-

nector

• Poor contact in

IG relay 1 (push

button start)

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

Model without

push button start

• Open or short

circuit to ground in

harness between

ECM connector

and ignition switch

connector

• Poor contact of

ignition switch con-

nector

• Poor contact of

ignition switch

• Faulty fuse (F/B

No. 12)

Model with push

button start

• Open circuit or

short circuit to

ground in harness

between ECM con-

nector and IG relay

1 (push button

start) connector

• Poor contact in

IG relay 1 (push

button start) con-

nector

• Poor contact in

IG relay 1 (push

button start)

• Faulty fuse (F/B

No. 12)

15WRX_STI_US_EN.book 484 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-485

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GN:DTC P2610 ECM/PCM INTERNAL ENGINE OFF TIMER PERFORMANCE

DTC DETECTING CONDITION:

• Detected when two consecutive driving cycles with fault occur.

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-232, DTC P2610 ECM/PCM INTERNAL ENGINE OFF

TIMER PERFORMANCE, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

GO:DTC U0073 CONTROL MODULE COMMUNICATION BUS OFF

NOTE:

For the diagnostic procedure, refer to LAN section. <Ref. to LAN(diag)-2, Basic Diagnostic Procedure.>

Step Check Yes No

1 CHECK FOR ANY OTHER DTC ON DISPLAY. Is any other DTC displayed? Check DTC using

“List of Diagnostic

Trouble Code

(DTC)”. <Ref. to

EN(w/o STI)(diag)-

85, List of Diagnos-

tic Trouble Code

(DTC).>

Replace the ECM.

<Ref. to FU(w/o

STI)-132, Engine

Control Module

(ECM).>

NOTE:

The soak timer IC

is built into the

ECM.

15WRX_STI_US_EN.book 485 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-486

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GP:DTC U0077 LIN COMMUNICATION BUS "ECM/PCM" OFF

DTC DETECTING CONDITION:

• Immediately at fault recognition

• GENERAL DESCRIPTION <Ref. to GD(w/o STI)-241, DTC U0077 LIN COMMUNICATION BUS "ECM/

PCM" OFF, Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION:

After servicing or replacing faulty parts, perform Clear Memory Mode <Ref. to EN(w/o STI)(diag)-61,

OPERATION, Clear Memory Mode.>, and Inspection Mode <Ref. to EN(w/o STI)(diag)-47, PROCE-

DURE, Inspection Mode.>.

WIRING DIAGRAM:

• Engine Electrical System ENGINE TYPE FA (WITHOUT PUSH BUTTON START) <Ref. to WI-162, EN-

GINE TYPE FA (WITHOUT PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

• Engine Electrical System ENGINE TYPE FA (WITH PUSH BUTTON START) <Ref. to WI-180, ENGINE

TYPE FA (WITH PUSH BUTTON START), WIRING DIAGRAM, Engine Electrical System.>

Step Check Yes No

1 CHECK DTC.

Check for DTC. <Ref. to EN(w/o STI)(diag)-46,

Read Diagnostic Trouble Code (DTC).>

Is U0077 displayed in «Present

fault»?

Go to step 2. Even if DTC is

detected, the cir-

cuit has returned to

a normal condition

at this time. Repro-

duce the failure,

and then perform

the diagnosis

again.

2 CHECK ECM CONNECTOR.

Check the connecting condition of ECM con-

nector.

Is the ECM connector correctly

connected?

Go to step 3. Connect the ECM

connector cor-

rectly.

B22

5678

10 11 12

1413 15 16

11 12

35 36

47 48

29 30

41 42

13 14

25 26

37 38

E158

B22

E158

EN-10819

ECM

BATTERY SENSOR

BATTERY

M/B No. 13

(BLACK)

15WRX_STI_US_EN.book 486 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-487

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

3 CHECK HARNESS BETWEEN BATTERY

AND BATTERY SENSOR CONNECTOR.

1) Turn the ignition switch to OFF.

2) Disconnect the ground terminal from battery

sensor. <Ref. to NT-5, BATTERY, NOTE, Note.>

3) Disconnect the connector from battery sen-

sor.

4) Disconnect the positive terminal of battery.

5) Measure the resistance of the harness

between battery positive cable terminal and

battery sensor connector.

Connector & terminal

Positive cable terminal — (B9) No. 1:

Is the resistance less than 1 Ω? Go to step 4. Repair the open

circuit in harness

between battery

positive cable ter-

minal and battery

sensor connector.

4 CHECK HARNESS BETWEEN ECM AND

BATTERY SENSOR CONNECTOR.

1) Disconnect the connector from ECM.

2) Measure the resistance of harness between

ECM connector and battery sensor connector.

Connector & terminal

(E158) No. 3 — (B9) No. 2:

Is the resistance less than 1 Ω? Repair the poor

contact of ECM

connector or bat-

tery sensor con-

nector.

Repair the harness

and connector.

NOTE:

In this case, repair

the following item:

• Open circuit in

harness between

ECM connector

and battery sensor

connector

• Poor contact of

coupling connector

Step Check Yes No

15WRX_STI_US_EN.book 487 ページ２０１５年２月１３日　金曜日　午前１１時２０分

EN(w/o STI)(diag)-488

Diagnostic Procedure with Diagnostic Trouble Code (DTC)

ENGINE (DIAGNOSTICS)

GQ:DTC U0101 LOST COMMUNICATION WITH TCM

NOTE:

For the diagnostic procedure, refer to LAN section. <Ref. to LAN(diag)-2, Basic Diagnostic Procedure.>

GR:DTC U0122 LOST COMMUNICATION WITH VEHICLE DYNAMICS CONTROL

MODULE

NOTE:

For the diagnostic procedure, refer to LAN section. <Ref. to LAN(diag)-2, Basic Diagnostic Procedure.>

GS:DTC U0155 LOST COMMUNICATION WITH INSTRUMENT PANEL CLUSTER

(IPC) CONTROL MODULE

NOTE:

For the diagnostic procedure, refer to LAN section. <Ref. to LAN(diag)-2, Basic Diagnostic Procedure.>

GT:DTC U0402 INVALID DATA RECEIVED FROM TCM

NOTE:

For the diagnostic procedure, refer to LAN section. <Ref. to LAN(diag)-2, Basic Diagnostic Procedure.>

GU:DTC U0416 INVALID DATA RECEIVED FROM VEHICLE DYNAMICS CON-

TROL MODULE

NOTE:

For the diagnostic procedure, refer to LAN section. <Ref. to LAN(diag)-2, Basic Diagnostic Procedure.>

GV:DTC U0423 INVALID DATA RECEIVED FROM INSTRUMENT PANEL CLUS-

TER CONTROL MODULE

NOTE:

For the diagnostic procedure, refer to LAN section. <Ref. to LAN(diag)-2, Basic Diagnostic Procedure.>

GW:DTC U1712 LOST LIN COMMUNICATION WITH BATTERY "1" MONITOR

MODULE

NOTE:

For the diagnostic procedure, refer to DTC U0077. <Ref. to EN(w/o STI)(diag)-486, DTC U0077 LIN COM-

MUNICATION BUS "ECM/PCM" OFF, Diagnostic Procedure with Diagnostic Trouble Code (DTC).>

15WRX_STI_US_EN.book 488 ページ２０１５年２月１３日　金曜日　午前１１時２０分